• Preheat the oven to 350°F (177°C). Use a 10-inch round cake pan that is at least 2 inches deep, or a 9-inch round cake pan that is at least 3 inches deep to ensure the batter has enough room to rise.

Make the Caramel Topping (In the Pan)

• Place the butter directly into the cake pan and set it in the oven while it preheating. Once melted, allow it to cook for about 2-3 minutes more, just until it turns golden and smells toasty, like a grilled cheese sandwich. Watch closely so it doesn’t burn.
• Carefully remove from oven. Stir in the brown sugar, pineapple juice, vanilla, and salt directly in the pan until glossy and combined.
• Return the pan to the oven for 1–2 minutes until the mixture begins to bubble slightly. Remove.
• Arrange the pineapple rings evenly over the caramel, then place a cherry in the center of each ring. Set aside.

Make the Cake

• In a bowl, whisk together cake flour, baking powder, baking soda, and salt. Set aside.
• In a large bowl, cream butter, oil, and granulated sugar until light and fluffy (2–3 minutes).
• Add eggs one at a time, mixing well after each. Mix in vanilla, buttermilk and pineapple juice. The batter may curdle, this is normal.
• Gently mix in the dry ingredients. Mix until just combined, do not overmix. Fold in the drained chopped pineapple.
• Carefully spoon batter over the arranged pineapples in the cake pan and smooth evenly. Bake for 45-50 minutes or until the a toothpick inserted in the cetner comes out mostly clean or with moist crumbs. Do not overbake.
• Remove from the oven and cool the cake in the pan for 10 minutes only, longer may cause the cake to stick to the pan.
• Run a knife around the edges. Place a serving plate on top and invert while still warm.
• Let caramel settle for a few minutes before slicing. Enjoy!