Sift flour, baking powder and salt into a bowl.
Rub in the butter with fingertips until it resembles breadcrumbs.
Add in milk tablespoon by tablespoon and knead into a rough dough.
Tip onto floured counter and continue kneading till smooth, adding flour and milk if the dough is too wet or too dry. Be careful not to overwork it.
Pick out a small piece of dough and, with a rolling pin, roll it out on a flour surface to get a thin circle 8cm in diameter.
Spread a teaspoon of sauce on the circle of dough, then place sausage (or other fillings) and cheese.
Seal the dough closed with wei fingertips. Twist the top a little so that it stays sealed.
Brush the tops with a little egg.
Bake in preheated oven at 180, or until a nice light brown.