In a big bowl, stir together the yellow cake mix, one egg, and melted butter. It’ll form a thick, dough-like mixture pretty quick. Press it evenly into the bottom of your prepared 9x13-inch pan.

Use your fingers or a spatula to smooth it out. This layer is the foundation, so make it nice and even.

In another bowl, beat the softened cream cheese until it’s creamy and lump-free. Add the eggs, vanilla, and melted butter, mixing until smooth. Gradually stir in the powdered sugar until you’ve got a thick, velvety batter.

This topping is the gooey heart of the cake. It should be pourable but not too thin.

Pour the cream cheese mixture over the base in the pan. Spread it out with a spatula so it covers everything evenly. It might look a little rustic, but that’s part of the charm.

The two layers will blend a bit as they bake. That’s where the magic happens.

Pop the pan into your preheated oven and bake for 40-45 minutes. The top will turn a light golden brown, and the center should still jiggle a bit. That wobble sets up as it cools, so don’t overdo it.

Pull it out when it looks just right. The smell alone will have you hooked.

Let the cake cool completely in the pan—about an hour or so. Once it’s set, cut it into squares for that classic St. Louis look. A dusting of powdered sugar on top is a nice touch if you’re feeling extra.

It’s tempting to dig in early, but waiting makes it easier to slice.