Barbara Aaron's Blueberry Cake: A perfect, simple summer cake

1 cup sugar
1/2 cup butter
2 eggs
1 cup sifted flour
1 tsp baking powder
salt
1 pt. blueberries
cinnamon
juice and peel of 1 lemon

Cram sugar and butter in food processor. Add eggs, one at a time; mix well after each. Add flour, baking powder, and salt all at once. Turn food processor on and off to mix (pulse). Put batter into 9" springform pan, sprayed with Pam. Sprinkle with cinnamon. Cover top with blueberries. Sprinkle them with lemon juice and grated lemon peel. Bake at 350˚ for one hour or until cake browns and center is set.