• Preheat oven to 350 °F. Grease or line an 8 X 8 inch pan with parchment paper or grease a cupcake tin.

Crumb Topping

• In a small bowl, mix brown sugar, granulated sugar, ground cinnamon, salt. Stir in the melted butter with a fork, then fold in flour making sure to keep the topping in large pieces. (If you over blend it will look more like a paste.) Set aside.

Crumb Cake

• In another bowl, combine flour, salt, baking soda and baking powder. Set aside.
• Beat the butter and granulate sugar on high speed until smooth and creamy, approximately two minutes depending on your mixer. Be sure to scrape down the sides since the mixture amount is small enough to be flung to the side often.
• Add eggs, vanilla and sour cream and beat on high. The mixture may look like it has not blended well but that is okay.
• Keep scraping the sides of the bowl while adding the dry ingredients. Beat on the lower speed until smooth but do not overmix. You are going for a more sticky, thick batter.
• Spread half the batter in your loaf pan or muffin tins.
• Add half the steusal topping and press down with your fingers or a spatula or large spoon until the topping has a flat appearance.
• Spoon in remaining cake batter mix and level.
• Add the remaining streusel, still pressing down in the batter mix until smooth.
• Bake for 45-60 minutes. Be sure to check at the 45-minute mark since different pans cook for different times. I used an 8 X 8 pan. If you use a cupcake tin, bake for 25 minutes then check every few minutes. Use the toothpick test in the center, it's done when the toothpick comes out clean. I covered the crumb cake at about 30 minutes to keep the topping from browning too much.
• Let cool on a wire rack for about 30 minutes prior to taking out. You can drizzle with an icing or dust with confectioner's sugar, although I like it just as it is.