Banana Poppy Seed Cake with Lemon Buttercream ~ snack time just got a whole lot more interesting with this unique combination of bananas, poppy seeds, and lemon ~ you can whip up this easy one bowl cake in no time.
Bake up this banana poppy seed cake when a good friend’s coming over for coffee, or there’s a last minute potluck at the office, or maybe you’ve been so good about eating super healthy for a couple of weeks now that you could use a treat. Whatever the excuse, I think you’ll be glad you gave it a shot. If you’re going to share it, be sure to have copies of the recipe ready to go, you’re gonna get asked.
This is a classic dense and moist banana cake with the footprint of a blondie ~ kicked up a notch or two with lots of crunchy poppy seeds and a tangy lemon frosting. Why should lemon and almond get all the fun when it comes to poppy seeds?
I don’t know why I haven’t thought to combine all these elements together before, they make for a cake that’s unusual but familiar at the same time.
I’m generous with this particular frosting, which has a similar tangy quality to a cream cheese frosting, but it’s even easier to whip up. You might know it from my Blueberry Zucchini Cake with Lemon Buttercream. It’s butter-heavy, and because of that I think it tastes best chilled, so I keep my cake in the refrigerator until I’m ready to eat.
No need to haul out the heavy equipment for this banana snack cake ~ just a whisk and a bowl will do fine.
It’s no secret that I love poppy seeds ~ I use them all the time, in everything from Lemon Poppy Seed Pancakes to Chicken Salad with Poppy Seed Mayonnaise. They just add that special touch to so many foods. I buy them in bulk, which means I always have some on hand to add to my recipes.
Ingredient spotlight: BULK POPPY SEEDS
If your local store doesn’t carry them, you can find poppy seeds in bulk, online, HERE. To store extra poppy seeds, put them in an airtight container in the refrigerator (6 mos) or freeze them, (1 year).
Reader Rave ~
“Absolutely amazing. I now have to gift the rest of it so I won’t eat anymore. I did use zest in the frosting. It was perfect.” ~ Leia
Ingredients
- 2 Tbsp unsalted butter, at room temperature
- 2/3 cup sugar
- 1/2 cup sour cream
- 1 large egg, room temperature
- 2-3 ripe bananas, mashed (to make about 3/4 cup mashed)
- 1/3 cup poppy seeds
- 1 tsp vanilla extract
- 1 cup flour
- 1/4 teaspoon salt
- 1/2 teaspoon baking soda
- 8 Tbsp (1 stick, 1/2 cup) unsalted butter, at room temperature
- 2 cups confectioner's sugar
- juice of 1 lemon (about 2 Tbsp)
- the tiniest drop of yellow food coloring (optional)
Instructions
- Set oven to 350F Lightly spray a 9x9 square baking pan. I like to line it with parchment paper so I can lift the cake out after baking for easy frosting and cutting.
- Cream the butter, sugar, and sour cream together until light and fluffy. Beat in the egg, mashed banana, poppy seeds, and vanilla.
- Whisk the flour, salt, and baking soda together and add to the wet ingredients. Mix until just blended.
- Turn the batter out into the pan and smooth out evenly. Bake for about 35 minutes, or until the top is just turning golden and the middle is set. A toothpick inserted in the center should be free of wet batter.
- Let cool on a rack completely before frosting.
- Make the frosting by beating the butter and sugar together with the lemon juice and food coloring, if using. Add a touch more juice if the frosting is too thick, or a little more sugar if too thin.
- I like to store the cake in the refrigerator, and it will keep for up to a week.
Make it your own ~
- Add the zest of the lemon to the frosting if you like.
- Substitute chopped walnuts for the poppy seeds.
- Substitute cream cheese for the butter in the frosting.
Don’t forget to pin this Banana Poppy Seed Cake with Lemon Buttercream
45 Comments
Mark Abel
August 12, 2019 at 11:24 amI made this yesterday, it’s very good. The lemon frosting goes wonderful with it. Great for using those old bananas. Cake part seemed really heavy, but we both loved it.
Sue
August 12, 2019 at 11:43 amThanks Mark :)
Divya
June 14, 2019 at 11:54 amHello! I am planning on making this for father’s day, and I was wondering if you could include a metric version of the ingredients? Also, how important is the sour cream? I don’t have any in the house, so I would be grateful for any other substitutions.
Sue
January 10, 2020 at 8:14 pmTypically I will substitute buttermilk, half and half, or even yogurt for sour cream if necessary.
Cecily
August 27, 2018 at 5:54 pmHi Sue,
Do you think this recipe would work in muffin form instead of a cake?
Thanks in advance!
Sue
August 27, 2018 at 6:06 pmI’m sure you could bake it that way Cecily, just be aware that it would be a dense type of muffin, not fluffy. The cake is sort of blondie-like in texture.
Verity
June 5, 2018 at 5:25 amHi, just wondering what kind of flour should be used for this; plain or self-raising flour?
Sue
June 5, 2018 at 6:55 amI use plain all purpose flour, Verity.
Eugene
May 10, 2018 at 2:15 pmLovely recipe thank you . I used ground almonds instead of flour and it was very moist and light.
Sue
May 10, 2018 at 2:38 pmThanks Eugene, that’s great to know about the gf option!
Karla
April 1, 2018 at 5:57 pmI made this to have for Easter morning breakfast since I wanted something special but we didn’t have much time before rushing off to church. I knew the frosting and bananas would add sweetness, so I halved the sugar. I don’t typically buy sour cream, but always have whole milk yogurt on hand, so that’s what I subbed. Poppy seeds, 1/4c. I replied to someone else that, yes, using gluten-free flour works nicely. The only other change was to use some of the frosting the I already made for a carrot cake, which was a maple cream cheese frosting. We all loved it! Such a nice variation of a banana bread. Adding this to my favorites!
Sue
April 2, 2018 at 7:03 amThanks for the feedback, Karla, and I’m glad to know that the yogurt worked well. I LOVE the sound of that maple cream cheese frosting, I’m definitely going to steal that idea from you ;)
Leia
March 15, 2018 at 4:03 amAbsolutely amazing. I now have to gift the rest of it so I won’t eat anymore. I did use zest in the frosting. It was perfect.
Lou
March 10, 2018 at 7:12 pmCan I use prepared poppy seeds in a tin or do you use dry ?
Looks so good
Sue
March 10, 2018 at 7:17 pmI used dry, Lou, but I wonder if you might be able to use the prepared seeds in place of the dry mixed with the cream. I don’t imagine it would taste quite as good, because the canned stuff has mostly added sugar.
Marianne
March 5, 2018 at 5:18 pmDo you know how to change the recipe to be gluten free? Sounds wonderful, but I don’t eat regular flour. Would love to make this for a family get together.
Sue
March 5, 2018 at 5:21 pmI’m not an expert on gluten free baking Marianne, but I do know that a good gf baking mix like Bob’s Red Mill’s can often be substituted for the flour, on a one to one basis, in lots of recipes so that’s worth a try. I don’t think the texture of this dense cake would suffer too much without the gluten. And I always go for the easiest solution before I get too complicated with substitutions.
Karla
April 1, 2018 at 5:54 pmI used my own gluten-free flour blend and it was great.
KRISTINA
December 22, 2019 at 7:32 pmKarla
would you mind sharing your blend? Thanks Krissy
Lori Weisberg
March 3, 2018 at 10:06 amHi Sue, You had me at poppyseed and lemon! So I made this yesterday, very good, thanks for the great recipe! Enjoying a piece right now!!
Sue
March 3, 2018 at 10:24 amThanks so much for the quick feedback Lori :)
Vicki Bensinger
March 3, 2018 at 4:29 amSuch a beautiful cake and definitely tempting for breakfast. I mean it does have bananas in it! Love the icing too.!
cakespy
March 3, 2018 at 3:01 amThis might be the most perfect flavor combination I have ever seen. I’m in love!
Laura | Tutti Dolci
March 1, 2018 at 5:47 pmThis is such a dreamy snack cake and I *love* the buttercream!
Marissa
March 1, 2018 at 12:10 pmThis flavor combination is seriously inspired!
Pamela Ferrante
March 1, 2018 at 9:44 amDoes the dry ingredients need sifted? This cake looks so good I am dying for a piece. I am going to make this over the weekend. I can’t use the poppy seeds, because my husband does not like them. I will make one with the seeds for my mom & me she loves them. Thanks for listening. Hope you and your family have a wonderful weekend.
Pamela
Sue
March 1, 2018 at 9:58 amNo Pam, you don’t need to sift them, but I do whisk them together to blend them.
Mary Ann | The Beach House Kitchen
March 1, 2018 at 7:24 amSnack time definitely got more interesting Sue! I love the combo of flavors here! On my baking list!
Melissa Griffiths
February 28, 2018 at 4:19 pmOooh I love poppyseed cake! The banana lemon combo sounds interesting!
Abbe@This is How I Cook
February 28, 2018 at 3:42 pmSue this really is a perfect cake. I also love poppy seeds and bananas. Lemon I’m still working on! But for something out of the ordinary…well you’ve created it right here!
Anna
February 28, 2018 at 8:34 amWhat a great combination of flavours! And I love that crunch you get from poppy seeds! Looks delicious, and that frosting on top- just heavenly!
John / Kitchen Riffs
February 28, 2018 at 8:25 amPoppy seeds and lemon? Say no more — love those two flavors together. The bananas are a bonus. :-)
Jill
February 28, 2018 at 8:02 amWishing I had a piece of this cake right now with my coffee. YUM!
Sue
February 28, 2018 at 8:12 amYou caught me, I’ve got a cold slice straight from the fridge sitting next to my coffee cup!
Lisa | Garlic + Zest
February 28, 2018 at 8:00 amThis cake looks so moist and rich I want to shove a (LARGE) piece into my mouth. And that frosting looks so creamy and luscious. I’m making this one, Sue.
Becca @ Amuse Your Bouche
February 28, 2018 at 7:45 amOmg that frosting looks so luscious! I love how thick you’ve spread it ;D
Sue
February 28, 2018 at 7:54 amIt’s all about the frosting to cake ratio ;)
Claire | Sprinkles and Sprouts
February 28, 2018 at 7:23 amOh this looks so moist and delish!!! Especially that icing. I want to take bite!!!
I also love the suggestion for swapping the poppy seeds for walnuts!! I think that would go down so well with my kids for afternoon tea!
Sue
February 28, 2018 at 7:29 amThis is a perfect tea cake, thanks Claire.
Jennifer @ Seasons and Suppers
February 28, 2018 at 4:53 amLoving the lemon buttercream here! And the banana cake looks perfect. Craving :)
Sue
February 28, 2018 at 6:59 amA little lemon buttercream never hurts ;)
Tricia @ Saving Room for Dessert
February 28, 2018 at 4:50 amThis lovely cake sure would be good with my coffee this morning! What a terrific flavor combination and that buttercream looks dreamy! Sharing and pinning :)
Chris Scheuer
February 28, 2018 at 3:57 amHmmm, would it be legal to have this for breakfast? It looks so good I want it now! And certainly easy enough to make before anyone else is awake! Pinning and sharing!
Sue
February 28, 2018 at 6:51 amOf course I was going to mention that I’ve already had it for breakfast…twice. But I thought that might be inappropriate ;)
Angie@Angie's Recipes
February 28, 2018 at 3:26 amI do love adding poppy into the banana cake batter. Your version with lemon buttercream looks fabulous, Sue.