Apple Walnut Upside Down Spice Cake | Food Stuff

Ingredients

• 1 cup apple slices (peeling optional)
• 1 tsp baking powder
• 1/4 tsp baking soda
• 2/3 cup brown sugar
• 1/4 tsp cinnamon
• 1 egg
• 1 1/3 cups all-purpose flour
• 1/4 tsp salt
• 2/3 cup sour cream
• 1/2 cup unsalted butter, softened
• 1 tsp vanilla
• 1/2 cup walnuts, chopped