2 1/2 cups (350 g) all purpose gluten free flour (I used Better Batter)
1 1/4 teaspoons xanthan gum (omit if your blend already contains it)
2 teaspoons baking soda
1/2 teaspoon baking powder
1/2 teaspoon kosher salt
1/2 cup (40 g) unsweetened cocoa powder (I have used both Dutch-processed and natural cocoa powders—both work fine)
1 1/2 cups (300 g) granulated sugar
2 eggs (120 g, weighed out of shell) + 1 egg yolk at room temperature, beaten
2 teaspoons pure vanilla extract
1 3/4 cups (14 fluid ounces) buttermilk, at room temperature (try souring some almond milk if you need dairy-free)
3 1/2 cups (400 g) confectioners’ sugar
1/2 cup (40 g) unsweetened cocoa powder (I have used both Dutch-processed and natural cocoa powders—both work fine but I much prefer the Dutch-processed)
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