2 tablespoons plus 1 teaspoon kosher salt, divided
2 1/2 cups shredded smoked Cheddar cheese, divided (1 1/4 cups for sauce, 1 cup for layers, 1/4 cup for cornflake topping)
10 pounds Idaho® Russet Potatoes, peeled and thinly sliced
1/2 cup cornflakes
Preheat oven to 350°F.
In a large saucepot, melt the butter over medium heat. Add the garlic and cook until tender, about 3 minutes.
Add the flour and gently stir, making a roux. Cook over medium heat until there is no raw flour taste, about 5 minutes; do not allow the roux to darken.
While stirring constantly, add the milk a little at a time, allowing the sauce to thicken slowly. Whisk in the paprika and 2 tablespoons kosher salt. Whisk in 1 1/4 cups of the smoked Cheddar, little by little, allowing the cheese to emulsify. Once all of the cheese has been incorporated, remove the pot from the heat.
Grease a 9” x 13” glass baking dish.
Line the bottom of the baking dish with a third of the sliced potatoes, allowing them to overlap a bit. Sprinkle 1/3 teaspoon kosher salt over top. Spread a third of the cheese sauce over the layered potatoes and top with 1/3 cup of the shredded Cheddar. Repeat layers until you have three total layers, ending with 1/3 cup of the shredded Cheddar. (It’s OK if all potatoes/cheese do not fit; save any remaining for another use.)
Cover the pan with aluminum foil and bake until brown and bubbly, about 1 1/2 hours.
In a small bowl, mix the cornflakes with the remaining 1/4 cup shredded Cheddar. Remove the potatoes from the oven and sprinkle the cornflake mixture on top. Return the pan to the oven uncovered and cook until the cornflakes are slightly browned and crispy, 5 to 10 minutes.