In a mixing bowl, combine 2 cups gluten-free flour, baking powder, and salt.
Cut in the cold butter until the mixture resembles coarse crumbs.
Stir in 1 cup milk until just combined. Drop dough by spoonfuls into a greased baking dish.
In a skillet, cook sausage until browned. Remove sausage and set aside.
In the same skillet, add 1/4 cup gluten-free flour and cook for 1 minute. Gradually whisk in 2 cups milk. Cook until thickened. Season with salt and pepper.
Pour sausage gravy over the biscuit dough in the baking dish.
Bake for 30-40 minutes or until biscuits are golden brown.
Let cool slightly before serving.
Notes:
This casserole is perfect for a hearty breakfast or brunch.