Preheat the oven to 350 degrees Fahrenheit and spray a 9-inch baking or springform pan with parchment paper or cooking spray.

Prepare the cake mix by stirring the yellow cake mix, whole milk, mashed bananas, vegetable oil, and large eggs together in a large bowl until completely combined. Set aside for now.

In a small bowl, whisk the light brown sugar with the melted butter until combined.

Pour the butter mixture into the bottom of the springform pan.

Place the sliced bananas in one layer, flat side down, onto the butter mixture. When sliding the bananas into place, press lightly.

Pour the cake batter into the springform pan atop the bananas.

Bake the cake in the oven for 30-35 minutes or until a toothpick comes out clean.

Remove the cake from the oven and run a knife along the edges of the springform pan to ensure easy removal.

Let the cake cool for 10 minutes before attempting to remove the cake.

Once the cake has cooled slightly, flip the cake onto a serving plate or cake plate so that the bananas will face up.

Gently remove the pan from around the cake.  Slice your cake before serving it warm or cooled.