Best Citrus Upside Down Cake Recipe - How To Make Citrus Upside Down Cake

Ingredients

• Cooking spray
• 4-5 citrus fruits, such as a variety of oranges, grapefruits, or lemons
• 1/2 c. granulated sugar
• 4 tbsp. butter, melted
• 1 1/2 c. all-purpose flour 
• 1 tsp. baking powder
• 1/2 tsp. kosher salt
• 1/2 c. (1 stick) butter, softened
• 1/4 c. packed brown sugar
• 1 1/2 tbsp. freshly chopped thyme
• Zest of 1 orange
• 2 large eggs 
• 1 tbsp. pure vanilla extract
• 3/4 c. buttermilk