Making creamy-smooth cheese sauces can be frustrating, particularly if you want to use quality cheeses such as aged cheddars or blue cheeses. This is because as cheese melts, it tends to separate into a gloopy mess of fat and water.

Classic solutions involve adding starchy flour or cornstarch to bind the proteins together, yet those same starches can muddle flavors. Processed cheeses melt smoothly thanks to added emulsifiers, usually sodium salt, which keeps the proteins together.

But as we learned in Nathan Myhrvold’s “Modernist Cuisine at Home,” this trick is easily replicated by the home cook.

The secret is sodium citrate, an inexpensive and widely available salt made from fruit-derived citric acid. A few grams added to warm milk allows almost any cheese (aside from hard cheeses like Parmesan) to melt smoothly, creating the perfect creamy sauce for pasta, vegetables or even just dunking hunks of bread.

We like a mix of sharp cheddar and Gruyère, but nearly any combination of strongly flavored cheeses works.

To make the sauce, in a large saucepan over medium, whisk together 11⁄4 cups whole milk and 10 grams sodium citrate (about 11⁄2 teaspoons) and bring to a simmer. Reduce the heat to low and slowly whisk in 4 cups grated cheese until smooth. Taste and season with kosher salt and ground black pepper. sells 50-gram packets of sodium citrate for about $6.

For more quick tips and product spotlights like this, read the rest of our Small Bites column from the November-December 2020 issue of Milk Street Magazine. Check out past issues here.

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