250g of mixed cheese (I used up leftovers from 5 different cheeses from xmas including smoked, brie, mature cheddar and parmesan)
1 leek thinly sliced
100g good quality bacon
1 teaspoon mustard powder or 2 teaspoons of ready mixed English or wholegrain depending on taste
750ml whole milk
2 cloves garlic smashed
Salt and black pepper to taste
Panko Breadcrumbs to give extra crunch in the oven.
Add the pasta to boiling salted water and cook for a minute or two less than the packet says. Drain and add a few nobs of butter to the pan of drained pasta to coat it and stop it absorbing too much of the cheese sauce and becoming bloated later on.
Chop the bacon into chunks and cook in the oven for around 10 minutes to brown slightly along with the sliced leeks then remove to cool.
Make a roux by adding a couple of nobs of butter to a warm pan with a about 2 tablespoons of flour and stir to mix. Cook for around a minute and start adding the milk gradually a bit at a time for it to thicken. Keep on a medium heat to warm the milk and for the roux to thicken for a few minutes.
The mixture will go from light to really start thickening very fast so take it off the heat when it starts to thicken and keep stirring. Add the mustard and cheese to the mixture and keep stirring to combine. I added a teaspoon of mild chilli powder at this point too along with some salt and pepper.
Taste the mixture and play around adding a bit more milk if it’s too thick, more cheese if not cheesy enough, or whatever else you want to give it a kick.
Add the cooled pasta to the cheese sauce mix and stir to make sure it’s evenly coated. Empty into a casserole dish, level out and sprinkle with more cheese. Scatter bacon and spring onion and the breadcrumbs if using these.
Either bake straight away in the oven on around 180C for around 20 mins or refrigerate and use later or the day after.