1 cup all-purpose flour
¾ teaspoon ground cinnamon
½ teaspoon baking soda
¼ teaspoon salt
¾ cup brown sugar
¼ cup unsalted butter, softened
1 large egg
¼ cup sour cream
¼ cup vanilla yogurt
1 teaspoon vanilla extract
2 cups diced Granny Smith apple
¼ cup brown sugar
¼ cup all-purpose flour
2 tablespoons unsalted butter, cut into small pieces
½ teaspoon ground cinnamon
Set the oven to 350 degrees Fahrenheit (175 degrees C). An 8-inch square baking dish should be generously greased and floured.
Produce the cake: In a bowl, combine the flour, salt, baking soda, and cinnamon.
Using an electric mixer, combine brown sugar and butter in a big bowl and beat until frothy and visibly lighter in color. Add the egg, then stir in the yogurt, sour cream, and vanilla until thoroughly combined. Add the flour mixture gradually, then fold in the apples. Batter should be poured into the baking pan.
Creating the topping Crumble the brown sugar, flour, butter, and cinnamon in a bowl using a fork. Dot over the batter.
Bake in the preheated oven for 35 to 40 minutes, or until a toothpick inserted in the center comes out clean. Take out and cool on a wire rack after baking.
If you don't have vanilla yogurt, substitute 1/4 cup additional sour cream or Greek yogurt with an additional dash of vanilla in the recipe.
1 8-inch coffee cake