From: Art of Gluten-Free Baking (http://artofglutenfreebaking.com)
Yield: 1- 10 inch cake
Preheat oven to 350 degrees F/180 degrees C/Gas Mark 4. Grease a 10 inch/25 cm pie pan with melted butter. I used a Pyrex glass pie pan.
In a small bowl, mix together flour, baking powder, and salt.
Place butter and 1 cup of the sugar in the bowl of an electric mixer fitted with the paddle attachment. Mix on medium high speed until light and fluffy—about 3 minutes. Add vanilla extract, beat until combined. Add egg and beat on medium high for 1 minute.
Reduce speed to low and add flour mixture and milk in alternating small batches, beginning and ending with the flour. Mix until combined.
Scrape batter into greased pan and smooth top. Place berries on top of the batter, cut side down. I try to do some sort of semi-artistic designed like a spiral.
Sprinkle the remaining 2 tablespoons of sugar over the berries.
Bake at 350 degrees F for about 1 hour, until the cake is golden brown and a tester comes out clean.
Cool in pan on wire rack. Serve in wedges.
Store at room temperature for up to 3 days, loosely covered.