Baked Macaroni and Cheese

Macaroni: 150g dry is enough for two reasonable portions here, not a family tray — the dish is small, which is partly why it works on a domestic hob and a small oven dish without anyone needing a kazan-sized pot. Any short tubular pasta that holds sauce in its hollow does the same job; shells or small shapes work, but macaroni's tube is what traps the sauce inside as well as around, so swapping to a long pasta like spaghetti changes the dish's whole texture, not just its shape.

Milk: full-fat, because the fat is what keeps the sauce from tasting thin and watery once the cheese and oven heat have both pulled moisture out of it. Semi-skimmed will thicken the same way — the starch doesn't care about fat content — but the sauce will taste leaner, more like wallpaper paste with cheese in it than something you'd want to eat with a spoon.

Butter and flour: this pair is the roux, and the ratio here — butter and flour in equal weight — is standard because equal parts means every flour grain has fat around it, which is what stops it clumping when the milk arrives. Butter specifically because it browns gently and has no competing smell; any flavourless fat with enough body to coat flour would do the same mechanical job, but you'd lose the faint nuttiness butter gives the base, which is small but real.

Cheddar: mature, not mild, and that's not snobbery, it's arithmetic. A sauce this plain — milk, butter, flour, nothing else sharp in it — needs a cheese with enough bite to stop it tasting like library glue. Mild cheddar melts the same way but brings less flavour per gram, so you'd need more of it to taste anything, and more cheese means more fat separating out under oven heat. Grate it yourself off a block rather than buying the pre-shredded bags — those are often dusted with anti-caking starch that can make the melt slightly grainy, a small thing but avoidable. Any firm, well-aged cheese that melts without turning to string — a mature Gouda, a Comté — will stand in for cheddar; a very young, wet cheese won't, because it has too much water in it and will loosen the sauce instead of thickening the top.

Salt and nutmeg: salt because milk and cheese both mute flavour until there's enough salt to carry it — taste the sauce before it goes in the dish, not after, because once it's baked you can't fix it. Nutmeg is the old trick for anything made with a milk-based sauce; it doesn't add sweetness so much as it cuts the flatness of boiled milk, a habit that goes back to when nutmeg was one of the few spices European kitchens had reliable access to and cooks leaned on it everywhere dairy needed waking up. A pinch, not a spoonful — it should be a presence you can't quite name, not a flavour you can point to.

The oven does the last job, and it's a dry one: it isn't cooking the inside of the dish any further in any meaningful way, it's driving moisture off the top layer of cheese until it browns. A domestic oven varies more than people admit, so treat the stated time as the earliest point to check, not a deadline — look for cheese that's gone from pale and shiny to blistered and gold at the edges, with the middle still slightly soft. If it's uniformly browned all over before that time's up, your oven runs hot and you'll want to check earlier next time; ovens don't lie evenly across their shelves, but they are consistent with themselves, so one bake teaches you the next.