Old-Fashioned Crumb Cake

This crumb cake is the kitchen-economy classic: one mixture of flour, butter, and cinnamon does double duty as both the cake’s base and its streusel-style crumb topping. You set aside a cup of the crumbs before mixing in the wet ingredients, sprinkle them back over the batter before baking, and end up with a snacking cake that’s tender below and craggy on top.

Sour milk is the secret. The acid reacts with the baking soda for lift and brings a mild tang that cuts through the cinnamon and nutmeg sweetness. Don’t have sour milk? The recipe makes its own (a teaspoon of vinegar stirred into a cup of regular milk, left to sit for 5 minutes until it curdles slightly).

It’s exactly the kind of cake to slice for an afternoon coffee break, pack into a lunchbox, or serve as a casual brunch dessert.

Pro Tips

• Cut the butter into the flour and cinnamon until it looks like coarse cornmeal. Pieces that are too large make a greasy topping; too fine and the streusel disappears into the cake.
• Reserve exactly 1 cup of crumbs for the top before adding any wet ingredients. Once the egg and milk go in, the texture changes and you can’t separate it back out.
• Don’t overmix once the wet ingredients go in. Overworked batter makes a tough crumb cake.
• Test for doneness with a straw or toothpick (the recipe is specific). It should come out clean from the center, not the streusel topping.
• Cool the cake in the pan on a rack so the bottom doesn’t get soggy from trapped steam.

Variations

• Stir 1 cup of fresh blueberries or chopped apples into the batter for a fruit-studded version.
• Add ½ cup of toasted pecans or walnuts to the streusel topping for crunch.
• Replace half the white sugar with brown sugar for a deeper, slightly molasses-tinged flavor.