Best Raspberry Peach Upside-Down Cake Recipe - How To Make Raspberry Peach Upside-Down Cake

Ingredients

• Cooking spray
• 1/2 c. (1 stick) melted butter
• 1 c. granulated sugar
• 2 large or 4 small ripe peaches, sliced
• 2 (6-oz.) packages raspberries
• 3 tsp. cornstarch, divided
• 2 2/3 c. all-purpose flour
• 2 tsp. baking powder
• 1 tsp. kosher salt
• 1/2 c. butter, softened
• 1/2 c. packed brown sugar
• 2 large eggs
• 1 tsp. pure vanilla extract
• 1/2 c. sour cream
• 1/2 c. milk