Ingredients

1/4 cup unsalted butter

1/4 cup plus 1 tablespoon all-purpose flour

3 cups cold milk

small pinch of nutmeg

1/4 teaspoon dry mustard

1/4 teaspoon cayenne, or to taste

1/4 teaspoon dried thyme, or few springs of fresh

1 1/2 teaspoons table salt, or to taste

Cheeses I used:

1/2 pound shredded extra-sharp cheddar cheese

1/4 pound shredded Gruyere cheese

For the potato chip topping:

1 tablespoon butter

1 bag (minus 6-7 chips) white cheddar kettle-style potato chips, crushed into medium-fine crumbs

1/3 cup finely grated Parmigiano-Reggiano (real Parmesan cheese)

2 tablespoons plain breadcrumbs

Preparation

https://www.youtube.com/watch?v=lPbmir3irxg