Cheese & Onion Pasties (if you'd rather not shop at Gregg's...)

Ok, so I'm going to be completely honest. Last Sunday, coming home from my friend's house, I had the most almighty hangover. 
I took the bus back to my local high street where my husband met me. Please bear in mind, before you judge me too harshly, that I was truly suffering! As I alighted from the bus I noticed that there was a greggs opposite.
The ghost of my teenage self spoke to me: "A pasty! That will sort you right out..."

MY TEENAGE SELF LIED. I bought cheese and onion pasties for both of us and eagerly took my first bite... of lukewarm, flavourless, textureless, over-seasoned, floury mush. Yuk. As we walked home I said that I could come up with a better pasty than that! So I did. Here it is, enjoy... with or without the hangover.

Cut three new potatoes into quarters and put on to boil until tender. I had the bleu d'auvergne variety, so that's why they are purple! Preheat the oven to 200°C and line a flat baking tray with oiled greaseproof paper.

Finely chop a large onion and a big stick of celery. Heat up a little oil in a frying pan and, if you like, snip in a slice of bacon (seriously one is more than enough) and cook until opaque before adding the onion and celery. Cook on a low heat to soften without browning.

After the onion and celery has softened add in a big handful of thinly sliced mushrooms and continue to cook on a low heat. On the side, grate a nice big pile of mature cheddar and a slightly smaller pile of parmesan. Then drain the potatoes, wait for the water to evaporate, and chop them into little tiny cubes before adding them to the vegetable mixture in the frying pan.

Once everything is cooked through, remove the pan from the heat and sprinkle over all the cheese then mix it in well, grind in lots of fresh black pepper and season to taste.
Cut a sheet of puff pastry into two rectangles, and place on the prepared baking tray. Divide the filling between the two sections, then fold the pastry over and press the seams together with a little beaten egg. Gently score the tops of the pasties and glaze with the rest of the egg.

Bake for about 20 minutes, until they are crisp and browned, and serve with a little salad and some really good ketchup (I like Mr Organic's version).

Don't be afraid to mess about with the ingredients - use what you have, that's what I did. I have plans to try doing another batch with mashed potato, onion and cheesy bechamel, which would result in a more traditional high street version.