The Barefoot Contessa demonstrates how she makes Blueberry Crumb Cake.
First, grease and flour the pan and set it aside. Put some soft butter into the mixer with some granulated sugar and beat until the mixture is light and fluffy. Add eggs, some lemon zest and sour cream. Next, sift together the flour, baking powder and baking soda. Add the dry ingredients slowly to the wet ingredients, being careful not to overbeat. Then stir in the blueberries and pour the batter into the prepared pan.
For the streusel topping, mix together melted butter, granulated sugar, brown sugar, cinnamon, nutmeg and flour. Crumble the topping over the cake and bake for 40 to 50 minutes.