Any-Fruit Coffee Cake

Combine apples and water in a saucepan over medium heat. Bring to a simmer; cover and cook until tender, about 5 minutes. Add lemon juice.

Mix 1 1/4 cups sugar and cornstarch together. Stir into the apples; cook and stir until very thick. Remove from heat and let cool.

Preheat the oven to 350 degrees F (175 degrees C). Grease a 9x13-inch baking pan.

Stir flour, remaining 1 cup sugar, baking powder, salt, cinnamon, and mace together in a large bowl. Cut in butter until mixture resembles fine crumbs.

Mix milk, egg, and vanilla together in a small bowl. Add to the flour mixture and blend until combined. Spread 1/2 of the batter in the prepared pan. Cover with the cooled apples. Drop remaining batter over the apples in small mounds. Spread.

Make streusel by mixing flour and sugar together. Cut in butter until crumbly. Stir in nuts. Sprinkle streusel over the cake.

Bake in the preheated oven until a toothpick inserted into the center comes out clean, 45 to 50 minutes.