Nachos, Properly Loaded, with a Homemade Cheese Sauce

The nacho is younger than you would guess and its inventor is a matter of record, which is rare for a snack this ubiquitous. In 1940, at a restaurant called the Victory Club in the border town of Piedras Negras, a maître d’ named Ignacio Anaya was faced with a group of American wives from the airbase across the river in Eagle Pass, arriving after the kitchen had closed. He improvised with what was to hand: fried tortilla triangles, grated cheese melted under the salamander, and a few slices of pickled jalapeño. He called them Nachos especiales, Nacho being the affectionate short form of Ignacio, and the dish took his name and never gave it back.

What Anaya made and what arrives at a cinema counter today are separated by about eighty years of drift, most of it downhill. Somewhere along the way the melted cheese became a pump-action orange fluid engineered to survive a heat lamp, and the careful triangles became a heap with a wet middle and a scorched top. I have eaten a great many bad nachos and I understand exactly how they fail. Getting them right is a matter of two decisions: making the cheese element behave, and building the pile so that every chip has a fighting chance.

The cheese sauce, and the science of keeping it smooth

Real cheese does not want to become a pourable sauce. Heat a handful of grated cheddar on its own and the fat weeps out and the proteins clench into a rubbery clump swimming in grease. The processed stuff pours because it has been chemically persuaded to, and my job is to persuade real cheese to do the same thing without the plastic aftertaste. A small béchamel is how I do it. The flour-and-butter roux, loosened with milk, gives you a starchy base that holds the cheese’s fat in suspension so it stays glossy instead of splitting.

The evaporated milk is a quiet secret worth explaining. It is milk with much of its water removed and its proteins concentrated, and those extra proteins are superb emulsifiers, coating the fat droplets and stopping them from pooling. A splash into the béchamel buys you a sauce that reheats without turning greasy, which matters because nachos are rarely eaten in one polite sitting. Grate the cheese yourself and grate it coarsely; pre-grated cheese is dusted with anti-caking starch that turns a sauce faintly gritty.

The twist: jalapeño brine instead of more salt

Here is the small change that makes people ask what you did. A cheese sauce made this way is rich and round and, left to itself, a little one-note. Most recipes reach for more salt or a shot of hot sauce to wake it up. I whisk in two tablespoons of the brine straight from the jar of pickled jalapeños. It carries acidity, salt, a gentle heat and a savoury vinegar tang all at once, and it seasons the sauce from the inside so the whole thing tastes brighter and more grown-up. That jar of brine is one of the most useful things in my fridge; I use it the way I use the sharp, herby lift of a salsa verde, to cut through richness that would otherwise sit heavy on the tongue. Taste as you add it, because jalapeño brands vary wildly in strength.

Building the pile so nothing goes soggy

A single deep mound of chips guarantees a soggy, cold centre and a burnt crown. The fix is to build in shallow layers, dressing each one, so the sauce and toppings are distributed through the whole tray rather than sitting on top. I use a large flat oven tray and spread the chips in an even scatter, sauce and bean them, then repeat. The chips themselves should be the thick, sturdy, restaurant-style triangles; thin supermarket crisps shatter and dissolve. Warm the beans before they go on, because a spoon of fridge-cold beans in the middle of the pile chills everything around it and the oven never quite recovers the temperature in the eight minutes you have.

Timing is the other discipline. The oven stage exists only to bring everything up to a happy, melting heat, and eight minutes at a moderate temperature does that without frying the exposed chips to bitterness. The fresh toppings — tomatoes, spring onions, coriander, soured cream — go on afterwards, off the heat, so they stay cool and crisp against the warm base. Cooked tomato on a nacho weeps water and dulls; raw diced tomato scattered at the end keeps its spark.

Method, step by step

Start the sauce. Melt 20g of butter in a small pan, stir in 20g of plain flour, and let the paste cook for a full minute until it loses its raw smell and turns faintly biscuity. Whisk in 250ml of whole milk and 50ml of evaporated milk a little at a time, keeping it smooth, then let it simmer gently for two minutes until it thickly coats a spoon. Pull the pan off the heat before the cheese goes anywhere near it, because boiling cheese is what splits it. Add 200g of grated mature cheddar and 50g of red Leicester in handfuls, whisking each one molten before the next, then whisk in a teaspoon of mustard powder, half a teaspoon of smoked paprika and two tablespoons of jalapeño brine. You want a sauce that ribbons off the whisk; loosen it with a splash of milk if it stiffens.

Heat the oven to 180C fan. Spread half of 200g of tortilla chips across a large tray, scatter over half a warmed tin of black beans, and drizzle with a third of the cheese sauce. Lay on the rest of the chips, the rest of the beans, and another third of the sauce, and warm in the oven for eight minutes until hot through. Take the tray out, pour over the last of the sauce, and finish with sliced pickled jalapeños, spring onions, diced tomato and coriander. Dot with soured cream, squeeze over a little lime, and put the wedges on the table. Eat immediately, while the cheese is still pulling into strands.

Make it your own

The template holds any number of loads. Leftover chilli or slow-cooked pork shoulder, warmed and spooned between the layers, turns this from a snack into a Friday supper. For something greener, char a couple of corn cobs, cut off the kernels and scatter them through. Guacamole belongs on top with the cold toppings, never baked. If you like real fire, a spoon of a proper chilli condiment goes a long way — the fermented depth of a homemade XO sauce is a spectacular, if unorthodox, addition dotted over the finished tray.

The cheese sauce is the part to keep in your back pocket. It reheats gently over a low heat with a splash of milk and never becomes the greasy sludge that reheated shop-bought cheese does, thanks to that evaporated-milk emulsion. Pour it over a jacket potato, fold it through macaroni, or use it as the base for a cauliflower cheese with real backbone. Once you can make cheese behave, a lot of comforting things open up, and it started with a maître d’ improvising for a hungry table an hour after closing.