Preheat your oven to 350°F (175°C).
Grease a 9x13-inch baking dish.
In a mixing bowl, combine softened cream cheese, sour cream, and powdered sugar until creamy.
Spread the cream cheese mixture evenly in the bottom of the prepared dish.
Sprinkle the lemon cake mix over the cream cheese layer.
Drizzle melted butter over the cake mix.
Pour lemon-lime soda evenly over the top.
Gently swirl the mixture with a fork to combine slightly.
Bake in the preheated oven for 35-40 minutes until golden brown.
Allow to cool slightly before serving.