Preheat the oven to 375°F (190°C) and grease a muffin tin.
In a large bowl, mix together the flour, baking powder, and salt.
Add the cooked sausage and shredded cheddar cheese, stirring to combine.
In a separate bowl, whisk together the eggs, milk, and melted butter.
Pour the wet ingredients into the dry ingredients and mix until just combined.
Spoon the batter evenly into the prepared muffin tin.
Bake for 20-25 minutes or until golden brown and a toothpick inserted in the center comes out clean.
Cool slightly before serving.