Harriet,

I don't have the bisquick recipe you are seeking, however, here is Martha Stewart's Recipe.

Blueberry Buckle

1/2 cup unsalted butter (1 stick), plus more for pan
2 cups all-purpose flour, plus more for pan
1 1/2 teaspoons baking powder
1/2 teaspoon salt
3/4 cup sugar
1 large egg
1 teaspoon pure vanilla extract
1/2 cup milk
5 cups wild or cultivated blueberries

1 recipe Streusel Topping (recipe follows)

Preheat oven to 350 Degrees F. Butter and flour springform baking pan, and set aside.

In a medium bowl, sift together the flour, baking powder and salt; set aside.

In the bowl of an electric mixer fitted with the paddle attachment, cream butter and sugar on medium speed until light and fluffy, about 3 minutes. Reduce mixer speed to low, add egg and vanilla. When combined, alternate adding reserved flour mixture and milk to mixer, beginning and ending with flour mixture. Remove from mixer; gently fold in berries.

Pour batter into prepared pan; sprinkle topping generously over cake. Bake 60 to 70 minutes or until cake tester comes out batter free. Remove cake from oven; leave in pan 10 minutes on a cooking rack. Remove from pan; let cool 15 minutes before serving.

Makes one 10-inch round cake or two 6-inch round cakes.

Streusel Topping
1 teaspoon ground cinnamon
1/4 teaspoon salt
1/4 cup packed light-brown sugar
1 cup all-purpose flour
6 tablespoons unsalted butter, room temperature

In a medium bowl, mix dry ingredients together; cut in the butter using a pastry blender or fork until fine crumbs form.

Using hands, squeeze together most of the mixture to form large clumps. Store, refrigerated, in an
airtight container, or sprinkle directly onto cake.

Makes enough for one 10-inch cake or two 6-inch cakes.

Enjoy!