I have seen 2 versions...I included both.

POPEYE'S BISCUITS

4 C. Bisquick
4 oz. sour cream
1 C. club soda (at room temperature)
1/2 C. (1 stick) margarine

Preheat oven to 375F.

Mix Bisquick, sour cream and club soda together. Pour onto floured surface and knead very lightly. Roll out to about 1/2-inch thickness and cut with cutter. Melt butter and pour half into a glass casserole dish. Place biscuits in dish and pour remaining butter over top of biscuits.

Popeyes® Buttermilk Biscuits
The secret is to cut cold butter into the mix with a pastry knife so that the biscuits turn out flaky and tender like the real deal.

2 cups all-purpose flour
1 tablespoon sugar
1 1/2 teaspoons salt
1 1/2 teaspoons baking powder
1/2 teaspoon baking soda
1/2 cup butter, cold (1 stick)
1/2 cup buttermilk
1/4 cup milk
To brush on top
2 tablespoons butter, melted

Preheat oven to 400 degrees.

Mix together flour, sugar, salt, baking powder, and baking soda in a medium bowl.

Slice cold butter into cubes and use a pastry knife or potato masher to cut butter into dry mixture until no large chunks of butter remain.

Add buttermilk and milk and stir with a spoon until dough forms. Roll out to 1/2-inch thick on a floured surface.

Cut biscuits with a 3-inch biscuit cutter and arrange on a lightly-greased or parchment paper-lined baking sheet. Bake for 22 to 24 minutes or until tops begin to turn light brown.

Remove biscuits from the oven and cool for a couple of minutes, then brush each biscuit top with melted butter.
Makes 10 biscuits.