This sweet, tender cake comes together in minutes and can be eaten for dessert, as a breakfast coffee cake or even a sweet snack. Fresh blueberries are perfect, but you can also use frozen berries — just bake for a few extra minutes to make sure the cake is done all the way through. The streusel topping adds some satisfying texture and contrast to the fluffy cake and soft blueberries.
For the cake:
1/4 cup butter, softened
3/4 cup white sugar
1 egg
1 teaspoon vanilla
2 teaspoons lemon zest, more if you prefer a stronger lemon flavor
1-1/2 cups flour
2 teaspoons baking powder
1/2 teaspoon salt
1/2 cup whole milk, plus about a tablespoon
1 tablespoon flour
1-1/2 cups fresh or frozen blueberries
For the topping:
5 tablespoons salted butter
1/4 cup brown sugar
1/4 cup white sugar
1/3 cup flour
1/2 teaspoon cinnamon
Cream the butter, sugar, egg, vanilla and lemon zest together until fluffy. In a separate bowl, combine the flour, baking powder and salt. Alternate between adding the dry ingredients and the whole milk to the butter mixture until just combined. In a separate bowl, toss the blueberries with the tablespoon of flour until evenly coated before gently stirring the berries into the batter. Spread the batter into a greased 8×8 pan.
To make the topping, combine all ingredients and mash with a fork (using a sharp knife can also help) until it has a crumbly texture. Sprinkle the crumble over the batter in the pan and bake for about 45 minutes at 350 degrees Fahrenheit, or until a toothpick or sharp knife comes out clean from the center of the cake.