Kyl Haselbauer has 20 years of experience working in fine-dining and modernist kitchens, including Bar Cotto and Anchovies &amp; Olives in Seattle. He is also the owner of Bright Spot, a café and coffee shop in Seattle.

Kyl Haselbauer

While you can argue about whether pommes aligot is the most delicious combination of potato and cheese in existence, it’s hard to argue that it isn’t the most impressive. A potato purée that you can stretch anywhere from 6 to 10 feet, as if it were some mutant melted mozzarella? Poutine could never.Getting pommes aligot to take on that texture is a little tricky, as you know if you’ve ever had a bad version. Done incorrectly, what you get is greasy and gluey cheesy mashed potatoes, with not a bit of stretch in sight.The texture of melted cheese basically depends on the behavior of casein proteins at different temperatures. At lower temperatures, the casein proteins in the cheese cross-link with one another with the assistance of calcium, which results in rope-like fibers that can both stretch and can stick to one another. As the temperature increases, the bonds holding the casein proteins together break and collapse, and the cheese takes on a fluid consistency. The addition of starches, fat, and salt—in the specific case of this recipe, that means the potato purée—improves the cross-linking between casein proteins, which further enhances the stretchy, stringy quality of the cheese, but you still have to be careful with temperature control. Heat the cheese/starch/fat/salt mixture too high, and the proteins will coagulate and the cheese will break; instead of stretchy cheese strings, you’ll have a starchy purée and a puddle of fat.Making a great pommes aligot, then, consists of two challenges: Creating a potato purée with just the right amount of fat, starch, and moisture that it will, when combined with cheese, readily produce that stretchy texture; and preventing the mixture of cheese and potato purée from being heated past the point at which that texture disappears completely.And as much as pommes aligot is a fun example of the wonders of culinary alchemy, in the end, the main reason you want to make it is that it’s delicious: rich, cheesy mashed potatoes with a uniquely stretchy and chewy texture.

Ultra-Cheesy Pommes Aligot