- 1 cup (130 grams) all-purpose gluten free flour
- 1/2 teaspoon baking powder * see note
- 1/2 teaspoon baking soda
- 1/4 teaspoon salt
- 60 grams unsalted butter, softened
- 2/3 cup sugar
- 1 1/2 Tablespoons sugar (extra)
- 1/2 teaspoon vanilla extract
- 1/2 teaspoon finely grated lemon zest (optional)
- 1 large egg
- 1/2 cup well-shaken buttermilk
- 1 cup fresh raspberries
Preheat oven to 200°C with rack in middle. Butter a 9-inch round cake pan.
Whisk together gluten free flour, baking powder, baking soda, and salt and set aside. In a larger bowl, beat butter and 2/3 cup sugar with an electric mixer at medium-high speed until pale and fluffy, then beat in vanilla and zest, if using. Add egg and beat well.
At low speed, mix in flour mixture in three batches, alternating with buttermilk, beginning and ending with the gluten free flour, and mixing until just combined. Spoon batter into cake pan, smooth the top. Scatter raspberries evenly over top and sprinkle with the extra 1 1/2 Tablespoons sugar.
Bake until cake is golden and a skewer inserted into center comes out clean, 20 to 25 minutes. Cool in pan 10 minutes, then turn out onto a rack and cool to warm, 10 to 15 minutes more. Invert onto a plate.
Make your own almost-buttermilk: No need to buy buttermilk especially for this or any recipe. Add one tablespoon [updated, as an astute reader pointed out that the larger amount is more common] of vinegar or lemon juice to one cup of milk and let it sit until it clabbers, about 10 minutes.
Note: Pure baking powders and sodas do not contain gluten but please double check the back of the packets you will use for those wanting a pure gluten free cake.