Preheat the oven to 375F. Line baking sheets with parchment paper.
Put the butter and chocolate in a microwave safe bowl and heat on high for one minute. Remove and stir to melt the chocolate. Heat a little bit more if needed. When the mixture is smooth, set aside to cool.
Add the eggs, sugar, and vanilla to the chocolate and beat until pale and thick. This will take a minute or so.
Blend in the baking powder and flour. Mix just until combined.
Let the dough sit at room temperature for about 15 minutes covered with a clean towel. It will thicken up as it sits.
Scoop out the dough with a rounded 1 inch scoop and put on a lined baking sheet. Keep the cookies 2 inches apart. If your scoops look wonky, wet your finger and smooth them out a little. Note: the batter will be quite tacky.
Bake for about 7 minutes. They will look puffed. After you take the baking sheet out of the oven sharply rap it on your counter ~ this will flatten the cookies. Let cool for a minute or two on the baking sheet before transferring to a rack. Note: Don't over bake these little cookies, you want them to be rich and fudgy. I found 7 minutes to work every time.
While the cookies bake make the filling. Beat the cream cheese and butter together with the milk or cream and vanilla, adding one cup of sugar at a time, beating well in between. You should have a thick but spreadable filling. If you need to thin it down, add a bit more milk or cream. To thicken it, add a bit more sugar.
When the cookies have cooled completely, make the 'sandwiches' by adding a healthy dollop of filling to one and topping with another cookie. Press down gently to get the frosting to the very edges of the sandwich.
Roll the edges of the filling in sprinkles or mini chocolate chips. Store the cookies in the refrigerator until ready to serve. I think they are best served chilled.
Nutritional information is provided as a courtesy and is an estimate only. This information comes from online calculators. Although The View from Great Island attempts to provide accurate nutritional information, these figures are only estimates.
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