Step 1 — Prepare the Caramel Apple Topping
Melt butter in a skillet or 9-inch cake pan over medium heat.
Stir in brown sugar until bubbly and fully combined.
Arrange apple slices evenly on top of the caramel.
Optional: sprinkle cinnamon or nutmeg over apples for a warm, spiced flavor.
Step 2 — Prepare the Cake Batter
In a large mixing bowl, cream together butter and sugar until light and fluffy.
Beat in eggs one at a time, then add vanilla extract.
Gradually mix in flour, baking powder, and salt.
Stir in milk or cream to form a smooth, pourable batter.
Step 3 — Assemble and Bake
Preheat oven to 350°F (175°C).
Pour the cake batter evenly over the apple-caramel layer in the pan.
Bake 35–45 minutes, or until a toothpick inserted into the center comes out clean.
Let the cake cool for 5–10 minutes before carefully inverting onto a serving plate.
Step 4 — Serve
Serve warm for gooey caramelized apples.
Optionally top with whipped cream, ice cream, chopped nuts, or a caramel drizzle.