8 tablespoons (112 g) unsalted butter, at room temperature
1 cup (200 g) granulated sugar
2 eggs (100 g, weighed out of shell) at room temperature, beaten
1 1/2 teaspoons vanilla extract
1 1/2 cups (210 g) all purpose gluten free flour (I used Better Batter)
3/4 teaspoon xanthan gum (omit if your blend already contains it)
1 1/2 teaspoons baking powder
1/2 teaspoon kosher salt
Juice and zest of 1 lemon (reserve 1 tablespoon juice for the glaze)
1/2 cup (113 g) sour cream, at room temperature
1 cup (115 g) confectioner’s sugar
More lemon zest for sprinkling (optional)
Preheat your oven to 350°F. Grease or line the wells of a standard 12 cup muffin tin and set it aside.
In a large bowl, place the butter and sugar, and beat until light and fluffy. Add the eggs, vanilla, lemon zest, and juice (reserving the final 1 tablespoons of juice for the glaze), and beat to combine. Add the flour, xanthan gum, baking powder, and salt, and mix to combine. Add the sour cream to the batter and mix until just combined. The batter will be light and fluffy, but not thin.
Divide mixture evenly among the muffin cups and shake into an even layer in each well of the pan. Place in the center of the preheated oven and bake for about 20 minutes, or until a toothpick inserted into the center comes out clean. Remove the pan from the oven and allow the cupcakes to cool for about 5 minutes before transferring to a wire rack to cool completely.
Once the cupcakes are cool, make the glaze. Place the confectioners’ sugar in a medium-size bowl and add about 1 1/2 teaspoons of the reserved lemon juice. Mix until you have a very smooth, thick paste. Add more lemon juice until you have a very thickly pourable glaze. Add the liquid slowly, because it’s much easier to thin it than to thicken if once you’ve added too much liquid. Pour or spoon the glaze over the cooled cupcakes, or dip the tops in the glaze. Sprinkle with the optional additional zest, and allow to set at room temperature.
Recipe originally published on the blog in 2009 (!). All photos, video, text new. Recipe instructions rewritten for clarity.