This is a quick, easy and tasty idea to do with fresh blueberries. You can use frozen but they tend to be watery and do not do this coffee cake justice.
Get the Recipe in pdf format here > Blueberry Sour Cream Coffee Cake
2 cups Flour
1 tbsp lemon zest
1 tsp baking powder
1 tsp baking soda
1/2 tsp salt
2/3 cup sugar
2 tbs powdered sugar for topping - optional
1/2 cup or 1 stick butter
1/4 cup vegetable oil
1 cup sour cream
2 eggs
1 cup blueberries
Preheat oven at 350 F - Spray a 9" x 9" glass pan with cooking spray - set aside
Combine flour, lemon zest, baking powder, baking soda and salt in a bowl. Set aside.
Beat butter, oil, sugar in a large bowl until light and fluffy, add eggs one at a time and beat well, add sour cream and beat well.
Gradually add flour mixture, mix well after each addition.
Pour into prepared glass baking pan, spread evenly in pan. Top with blueberries.
Bake for about 55 minutes, or until golden brown on top and toothpick inserted into middle comes out clean.
Cool in pan on wire rack. Sprinkle with powder sugar.