Crunchy cinnamon-and-sugar streusel plus a sweet vanilla glaze top classic homemade coffee cake. Mmm. There's also a pretty great variation using cranberry and raspberry, at the bottom of the recipe. Give them both a try.
Preheat oven to 375°F (190°C). Coat bottom and side of a 9-inch (23 cm) springform pan or 9-inch (23 cm) square pan with butter, shortening, or cooking spray.
In a small bowl, mix sugar, flour, and cinnamon together. Cut in butter with a fork until crumbly.
Make the coffee cake
In a large bowl, combine all of the coffee cake ingredients except the blueberries. Using a spoon, mix vigorously for 30 seconds. Fold in blueberries.
Spread batter in prepared pan. Sprinkle with crumb topping.
Bake until a toothpick inserted in the center comes out clean, 45 to 60 minutes. Cool cake in pan for 10 minutes, then remove the side of the pan, if using a springform pan.
Make the vanilla glaze
In a small bowl, mix glaze ingredients until smooth and thin enough to drizzle. Drizzle over warm coffee cake.
Notes
VARIATION
CRAN-RASPBERRY COFFEE CAKE: Prepare as directed—except substitute 1 cup fresh or frozen raspberries and 1 cup fresh or frozen cranberries, sliced in half, for the blueberries.