Ingredients
500g pasta, fusilli or penne
50g butter
50g plain flour
700ml milk
1 chicken (or vegetable) stock pot
40g parmesan
80g cheese (red Leicester, double Gloucester, cheddar etc), grated
2 x 145g tin of tuna
1 x 20g bag of ready salted crisps
Aromat (or Salt)
Freshly ground white pepper

Method
Preheat the oven to 190c.

Put a pan of heavily salted water on to boil. Put the pasta into the boiling water and cook according to the package instructions, this will be somewhere between 10 and 15 minutes depending on the shape you pick.

Meanwhile melt the butter in a saucepan and when melted, stir in the flour and cook out for 1 minute, stirring all the time to stop it burning.  Add the milk gradually so that you don’t get any lumps and stir until it is thoroughly combined.  Cook for 3-5 minutes until the sauce is thick.  Be patient with this, if it’s not thick carry on cooking for a few minutes longer.  Add the stock pot and stir through until melted.  Turn off the heat and add the cheese.  Leave for 1 minute then stir through.

When your pasta is almost cooked take a cup of the pasta water out and put to one side.  If your sauce is very very thick then add half a ladle of the pasta water and stir through.

Put the pasta into the sauce and thoroughly stir to combine.  If the sauce looks too thick then add a little more of the pasta water until it slackens and just coats the pasta nicely.  You might not need the pasta water so just see how you go.  Add the tuna and very gently stir through so you don’t break it up too much.  Check for seasoning and add some Aromat (or salt) if needed and a little white pepper and stir through.  Transfer to an oven proof dish.

Crush the crisps briefly so they are different sizes and scatter over the top of your oven dish and bake for 20 minutes.