Made with buttermilk, brown sugar, and fresh fruit, this strawberry rhubarb coffee cake recipe is an early summer family favorite.
Note: You can find freeze-dried strawberries in the dried fruit or natural foods aisle of your grocery store. If they are unavailable, you can substitute regular strawberries, sliced lengthwise.
2/3 cup granulated sugar
1 3/4 tablespoons salted butter, melted
Make the topping: In a small bowl, stir together the sugar and butter until crumbly. Set aside.
Butter for the pan
1 cup buttermilk
1 cup firmly packed light brown sugar
1 large egg
1 teaspoon vanilla extract
2 1/2 cups all-purpose flour, plus more for the pan
2/3 cup vegetable oil
3/4 teaspoon table salt
1 teaspoon baking soda
1 teaspoon baking powder
1 1/3 cups rhubarb (1/2-inch slices), from 3–4 stalks, depending on size
3/4 cup chopped strawberries
Strawberry slices (either fresh or, for extra crunch, freeze-dried), for garnish
Preheat oven to 330° and set a rack to the middle position. Butter and flour a 9-inch springform pan.
Make the cake: In a medium bowl, stir together the buttermilk, sugar, egg, and vanilla until smooth. In the bowl of a standing mixer, combine the flour, oil, and salt; mix on low until crumbly (scraping down the sides of the bowl once). Add the buttermilk mixture to the flour mixture and beat on medium until smooth. Add the baking soda and baking powder, and beat for several seconds. Fold in the rhubarb and strawberries by hand. Pour the batter into the prepared cake pan and sprinkle evenly with the sugar topping.
Bake the cake until a tester inserted into the center comes out clean, 50 to 60 minutes. Just before serving, arrange the strawberry slices in a circle on top, with a few in the center. Serve warm or at room temperature.