Savoury Beef Tartlets/Tarts

Next one up is my savoury beef tarts. I wanted to make pies at first but on second thoughts, that might be a little too much.

Ingredients:
Fillings:
300g good quality minced beef
6 button mushrooms
1 small onion
A small dollop of butter
Oregano
2 tbsp Worchester Sauce
Salt and pepper to taste
2 slices of processed cheese
4 tbsp of tomato sauce

Pastry:
120g butter
160g all purpose flour/wheat flour
4 tbsp of ice water

* Marinate beef with Worchester sauce, salt and pepper and leave in the chiller*

1) Do the pastry first. Crumb the butter and flour together (I prefer hand but you can use food processor for a speedier way). Add in the ice water bit by bit i.e. tablespoon by tablespoon and you can adjust the amount accordingly. The consistency you are looking for is the dough-like smooth texture. Do be careful not to work the dough too much.
2) Keep in fridge until you wanted to roll them out. Keep chilled for at least an hour.
3) Roll into about 1/2 inches thick and cut them out in circles before tapping them into greased 9-hole muffin tin. Mine is about 4" in diameter and I get about 11 tart pastries when I'm done.
4) Poke holes into the bottom of the pastries when you're done before you bake them. If you don't plan on eating them yet, just leave them in the tin and keep them back in d fridge. :)
5) Bake for about 15 minutes or until brown at 200 degree Celsius. Pat them down using a spoon or fork in the middle of baking so the tarts maintain their shape.

6) Chop the onions finely.
7) Cube the button mushrooms.
8) Heat the skillet and drop in the butter.
9) Fry the onion until fragrant before adding in the mushrooms and continue stirring.
10) Add the beef and add the tomato sauce when the beef is browned.
11) Add in the oregano.
12) Switch off the fire and stir in the processed cheese.
13) Scoop about a tablespoon of filling for each tart and distribute the remaining amongst them.