1 can (16 oz.) lemon pie filling
1 package (15 oz.) yellow cake mix
4 oz. cream cheese, cubed
1/2 cup (1 stick) unsalted butter, thinly sliced
Preheat the oven to 350º F and lightly grease a square baking pan with butter or nonstick spray.
Pour the lemon cake filling into the bottom of the greased baking dish, making sure to spread it out in the corners.
Cover with 1/2 cake mix, place cream cheese cubes evenly on top, then sprinkle with remaining cake mix.
Take the butter pats (cut as thinly as possible) and place them in a single layer over the cake mix, trying to cover as much of the cake surface as possible.
Place the baking sheet in the oven and bake for 35-40 minutes, or until the toothpick inserted in the center comes out clean.
Remove from oven and let cool 15-20 minutes before serving.