This is one of my favourite comfort meals, quick to assemble, using ingredients that I generally have kicking about the house, and can just be slung in the oven and forgotten about, left to slowly pull itself together in a haze of blissful creamy soft salty rich glorious goodness. I’ve just polished off my second bowl of it, and frankly, it’s too good not to share with you all, so here it is. It’s easy to make it vegan – replace the hard strong cheese and mozzarella with Violife or something similar, and the milk with coconut or almond or soya milk, depending on what you prefer. It’s easy to throw together, and the reward of a deep bowl of melting goodness far outweighs the minimal effort involved in making it. I consider this an essential part of my repertoire these days, and barely a week goes by without it. It freezes beautifully, too, so do double the recipe and sling some of it to one side for a lazy day.
Serves three people, or two particularly hungry ones, at 42p each
1 onion, 9p (90p/1.5kg, Sainsburys)
1 tbsp sunflower oil, 3p (£3/3l)
A pinch of salt, 1p (25p/1kg, Sainsburys Basics)
1 tbsp flour, 2p (65p/1.5kg)
400ml milk – or vegan equivalent, 18p (44p/1l)
150g mushrooms, 36p (97p/400g, Sainsburys Basics)
Half a ball of mozzarella, 22p (44p, Sainsburys Basics)
Scant edge of a teaspoon of mustard, <1p (45p/180g, Sainsburys Basics)
200g pasta (I used ‘gigli’ as it was a birthday present, but am pricing it up as a cheaper option as fancy frilly pasta is not essential!) 14p, (35p/500g Sainsburys Basics)
15g hard strong cheese, 18p (£2.30/200g, Sainsburys Basics)
A slice of bread, 2p (40p/22 slice loaf, Sainsburys Basics)
First peel and finely chop your onion and sling it in a saucepan with a slug of oil. 
Cook on a gentle heat for a few minutes to soften, season with salt, and sprinkle in the flour. Mix briskly so that the flour coats the onions.
Add a liberal splash of milk and beat well to form an oniony paste. It doesn’t look all that at the moment, but don’t worry, it’s going to get better. Add another splash of milk, and another, keeping it moving so it doesn’t catch and burn, nor go stiff and sticky. Stiff and sticky certainly have their uses, but neither of them are needed in this particular scenario. Repeat until all the milk is used up; it will be quite runny at this point, but it will firm up in the oven later.
Finely slice your mushrooms, or break them up by hand – I’ll be honest, I like to just smash them between my thumbs, especially at the end of a stressful day. Try it, you might like it. However you choose to dismember them, add them to the pot and stir through. Add your cheese (or cheese equivalent), dollop in the mustard, crank the heat up, and stir through until melted.
Remove the pan from the heat, and fold in the pasta. (Folding in is a cookery term that basically means ‘gently stir it without mooshing it about too much’.) Tip it into an ovenproof dish, making sure the pasta is pretty much covered in the sauce, add more cheese on top, and optional breadcrumbs if you like that kind of thing, and pop it in the oven at 180C for 45 minutes.
Serve, or if you’re anything like me, eat it from the pan in front of the telly to both feel ludicrously decadent, and save on washing up.
I have made this in the past with garlic and grated celery added to the base, both of which add a real depth of flavour, but as this is a frugal cookery blog, neither are particularly essential to the main recipe, but they definitely add a little special something, so if you have either kicking around, give them a go. Just add them at the same time as the onion, a couple of garlic cloves and a stick or two of celery ought to do it. A pinch of chilli doesn’t go amiss, neither does a shake of nutmeg, and a handful of spinach (fresh or frozen) is always a good idea. But if you don’t have or like any of the little tweaks, seriously, it’s a pretty stunning dinner all by itself.
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