• Put the sugar and zest in the food processor and pulse/process until the zest is fully incorprated and the sugar is pale yellow and fragrant. It will have the texture of brown sugar.
• Add the flour, baking powder, baking soda and salt to the bowl and pulse to combine well.
• Drop the pieces of cold butter into the machine and pulse about 20 times to fully incorporate the butter. The mixture should have an even crumbly texture.
• Add the cream and extract and pulse until the dough begins to come together. It will look crumbly, but moist, without dry flour remaining.
• Scoop the dough with a 2 ounce cookie or ice cream scoop onto a parchment lined baking sheet. Put the sheet in the freezer for 15 minutes.
• Meanwhile preheat the oven to 400F.
• Bake the cold scones for 18 minutes, or until just starting to turn golden. The centers may look moist, but will firm up as they cool. Try not to overbake these small scones.
• Let the scones cool on a rack completely before glazing.

to make the glaze

• Combine the sugar with just enough lemon juice to make a thick pourable glaze. Start with 2 tablespoons and go from there. Stir until there are no more lumps left.
• Dunk each scone headfirst into the glaze, then set them on the rack to allow the glaze to set up. You can test one scone to make sure you've got the glaze the way you like it. Add more sugar for a thicker glaze, and more lemon to thin it down.
• Store the scones, covered in foil or with a cake dome, at room temperature for up to 2-3 days.