This streusel coffee cake is tender and moist with the best crumble topping! Add your favorite mix-ins, including berries, pecans, chocolate chips, and more.
Prep. Preheat oven to 350ºF. Line an 8-inch cake tin or a loaf pan with parchment paper and set aside.
Mix the cake batter. In a large mixing bowl, combine flour, baking powder, light brown sugar, melted butter, eggs, and yogurt. Mix until thoroughly combined. Gently fold in the berries.
Fill the pan. Pour the mixture into the prepared pan and set aside.
Make the topping. Add cold butter, oats, and light brown sugar to your food processor; pulse a few times until the mixture is crumbly. Sprinkle streusel on top of the cake batter.
Bake. Bake for 75 to 80 minutes, or until a toothpick inserted in the center comes out clean. Remove from oven and let stand 10 minutes.
Cool. Invert cake onto a cooling rack and let it completely cool before cutting and serving.
Notes
How to store: To keep for several days, wrap the cooled cake with plastic wrap and aluminum foil. You can also freeze it this way, or you can let it stand in a cool, dry place.