Preheat oven to 400 degrees. Prick sausages with fork. Place in baking pan and bake about 8 mins, long enough for fat to run out, grease pan and let pan get hot.
Mix flour, baking powder, and salt. Beat eggs, milk, and butter. Add to dry ingredients and beat until bubbles rise to the surface Pour over sausages and bake 30-35 mins longer, until batter is light brown and puffed.