Preheat your oven to 450°F.
In a large mixing bowl, whisk together the flour, baking powder, salt, black pepper, and garlic powder until well combined.
Stir in the shredded cheddar cheese and cooked sausage until evenly distributed.
Make a well in the center of the dry ingredients and pour in the buttermilk and melted butter.
Gently mix until just combined; be careful not to overmix. The dough will be slightly sticky.
Pour the dough into a greased 9x13-inch baking dish, spreading it evenly.
Bake in the preheated oven for 20-25 minutes, or until the top is golden brown and a toothpick inserted in the center comes out clean.
Let the biscuits cool for a few minutes before serving. For extra flavor, brush the tops with additional melted butter before serving.