Mix the sausage meat, salami, onion and grated cheese together with the basil and a little pepper.
Sift the flour, baking powder and a pinch of salt into a bowl and rub in the butter. Bind to a soft dough with the milk.
Roll out the dough to form a rectangle about 30cm x 18cm and spread the mixture over the surface.
Roll up from the narrow edge and cut into eight pieces using a large sharp knife. Try to cut using a sawing action rather than pressing too heavily on the mixture.
Place cut side down on a lightly oiled baking sheet.
Bake for about 15 minutes, then leave to cool on a wire rack.