Preheat your oven to 450°F (232°C).
Add the baking mix, sour cream, and 7Up to a large mixing bowl and stir until just combined.
Sprinkle a little additional Bisquick on your counter or cutting board. Gently knead the dough and pat it out flat.
Cut the dough into biscuits using a round cutter or glass.
Pour the melted butter into a 9-inch square baking dish and place the biscuits on top of the butter.
Bake for 12–15 minutes or until golden brown.
Remove from oven and serve warm.