I'd do what Krystals said. Cut the steaks into smallish cubes (small bite size for pies is good I think), dust in flour with a little pepper and sweet paprika, brown on all sides, then add some fried finely chopped onion (I cook it in the pan before the steak) and enough water to make a thick gravy. Don't add too much water to start with (remember, you can always add, but you cannot take away), and some gravy powder would add some extra colour, flavour, and thickening too. Cook, covered, on low heat until meat is cooked through. What you want is a really thick casserole, so if you have a favourite casserole dish, you can basically just put it into pies! Happy cooking.

Oh yeah, I use short crust pastry on the bottom of the pies, and puff only on the top, brushed with egg wash (an egg beaten with a little milk) to brown.