Preheat oven to 400°**

Line bottom of a buttered (or greased with shortening) 8 x 2″ round cake pan*** with 2 rounds of parchment paper, then butter parchment, dust pan with some flour and turn upside down over your sink and tap, knocking out excess flour.

Arrange the blackberries and raspberries in one layer in the cake pan. Sprinkle berries with the 1 1/2 tablespoons sugar you have set aside and shake pan to help distribute sugar.

Whisk together 1 cup flour, baking soda,and salt in a bowl. Beat together butter and remaining 1/2 cup sugar in a large bowl with an electric mixer at high speed until light and fluffy, about 2 minutes. Add the egg and vanilla and mix at low speed until just incorporated. Alternately add the flour mixture and the buttermilk in 3 additions, mixing at low speed until just blended together.

Spoon the batter over the berries and use a spatula to smooth the top. Bake in the middle of the oven until top is golden and a tester comes out clean, 30-35 minutes.

Run a knife around the edge of the pan and invert a large plate over pan. Use pot pads to hold pan and plate together and flip the cake onto the plate. Carefully peel off the waxed paper and you are ready to serve.

*Buttermilk — if you don’t happen to have buttermilk (and I didn’t) you can put 1 1/2 tsp. white vinegar in a 1/2 cup and add milk. Give it about 5 minutes and you will have buttermilk.

**400° temperature I thought was too hot. Most cakes cook at 350° so I cooked it at 400° for about 13 minutes and then turned it down to 350° for the remainder of time.