Crumb Cake Recipe For the crumbs: 2 1/2 cups all-purpose flour 1 cup light-brown sugar 1/4 teaspoon salt 1-1/2 tsp. cinnamon 1 cup (2 sticks) butter, melted and cooled powdered sugar to top with Cake 1 large egg 1 tsp vanilla extract 1/4 cup milk 1/4 cup sour cream 5 Tbsp butter, softened 11/2 cup all-purpose flour 3/4 tsp baking powder 1/8 tsp baking soda 1/4 tsp salt 1/2 cup granulated sugar Preheat oven to 350 degrees. Butter an 8 by 8-inch baking dish then lightly flour For the crumbs: In a mixing bowl whisk together brown sugar, cinnamon and salt. Pour in melted butter and stir to combine. Slowly add ...