Blueberry Crumb Cake Squares

1 10x15 inch jelly roll pan, buttered

Cake:

½ lb (2 sticks) unsalted butter, softened

1 ½ C granulated sugar

3 eggs plus 3 egg yolks

2 tsp vanilla extract

¼ C milk or buttermilk

2 ½ C bleached all-purpose  flour

2 tsp baking powder

1 quart blueberries (any berry) picked over and dried

Crumb topping:

2 C bleached all-purpose flour

1/3 C granulated sugar

1/3 C brown sugar

½ tsp ground cinnamon

¼ tsp grated nutmeg

12 T (1 ½ sticks) unsalted butter, melted

Set rack in the middle level of the oven and preheat to 350.

For the cake batter, in a large mixing bowl, beat the butter and sugar until they’re soft and light. Add the 3 eggs one at a time, beating well after each addition. Beat in the vanilla. In anther bowl, stir the yolks into the milk. Sift together the flour and baking powder and stir into batter in 3 additions, alternating with the yolks and milk, beginning and ending with the flour, spread the batter in the prepared pan. Scatter Berries in evenly over the batter, and press them in gently. 

To make the crumbs, mix the dry ingredients in a bowl. Stir in the melted butter. Rub the mixture to coarse crumbs by hand. Scatter the crumbs over the berries as evenly as possible. 

Bake for 50-60 min till batter is firm and crumbs are well colored. Cool cake on rack.