1 medium granny smith apple, peeled and chopped/ 4½ ounces
TOPPING
¾ cup packed light brown sugar/ 5¼ ounces
1 cup chopped walnuts/ 4 ounces
1 teaspoon cinnamon
Instructions
Preheat the oven to 350° F. Grease a 13 x 9 inch pan or two 8-inch round cake pans with melted coconut oil, or spray with a non-stick cooking spray.
Mix the butter and sugar together until light and fluffy. Add the eggs and sour cream and combine thoroughly. In another bowl whisk together the flour, baking powder, nutmeg, salt, and baking soda and add to the batter mixture. Stir until just combined. Fold in the blueberries and apples and pour into the pan(s), dividing the batter evenly if using two pans.
Mix the brown sugar, chopped walnuts, and cinnamon together and sprinkle evenly over the batter.
Bake for 30-35 minutes until a toothpick inserted in the center of the pan(s) comes out clean.