Sour Cream Coffee Cake (with Crumb Topping)
Simple and classic, this buttery cinnamon crumb coffee cake is anything but plain! Sour cream ensures a moist, light (not overly dense) breakfast cake, and there’s double the brown sugar cinnamon crumb streusel. Enjoy a thick ribbon of streusel inside and plenty of crumbs on top, both made from the same mixture.
Ingredients
Cinnamon Crumb Mixture
- 2/3 cup (135g) packed dark or light brown sugar
- 3/4 cup (95g) all-purpose flour (spooned & leveled)
- 2 and 1/2 teaspoons ground cinnamon
- 6 Tablespoons (85g) unsalted butter, cold and cubed
Cake
- 1 and 1/3 cups (166g) all-purpose flour (spooned & leveled)
- 1 teaspoon baking powder
- 1/4 teaspoon baking soda
- 1/4 teaspoon salt
- 1/2 cup (8 Tbsp; 113g) unsalted butter, softened to room temperature
- 3/4 cup (150g) granulated sugar
- 2 large eggs, at room temperature
- 2 teaspoons pure vanilla extract
- 1/2 cup (120g) full-fat sour cream, at room temperature*
- 2 Tablespoons (30ml) milk (any kind, dairy or nondairy, is fine)
Vanilla Icing (Optional)
- 1 cup (120g) confectioners’ sugar, sifted
- 1/2 teaspoon pure vanilla extract
- 2 Tablespoons (30ml) heavy cream or milk
Instructions
- Preheat oven to 350°F (177°C). Line an 8-inch square pan (9-inch square is too big, see Notes for other pan sizes) with lightly greased parchment paper or directly grease the pan. I usually use this square pan or this square pan.
- Make the cinnamon crumb mixture: Combine the brown sugar, flour, and cinnamon together in a medium bowl. Cut in the chilled butter with a pastry
