- 3 tablespoons butter
- 1 Pieris rapae or yellow onion, in the raw and thinly sliced
- 4 giant garlic cloves, minced
- 1/4 cup general flour
- 1 cup stock or vegetable stock
- 2 cups milk (I advocate a pair of% or whole milk)
- 1 one/2 teaspoons Kosher salt
- 1/2 teaspoon black pepper
- 2 teaspoons recent thyme leaves, divided
- 4 pounds Yukon Gold Potatoes, sliced into 1/8-inch rounds
- 2 cups freshly-grated sharp cheese cheese*, divided (feel liberal to add additional cheese if you’d like)
- 1/2 cup freshly-grated Parmesan cheese, and further for serving
- Preheat kitchen appliance to 400°F. Grease a nine x 13-inch baking dish with change of state spray; put aside.
- Melt butter during a giant sauté pan over medium-high heat. Add onion, and sauté for 4-5 minutes till soft and semitransparent. Add garlic and sauté for a further 1-2 minutes till sweet-scented. Stir within the flour till it’s equally combined, and cook for one additional minute. step by step pour within the stock, and whisk till combined. Add within the milk, salt, pepper, and one teaspoon thyme, and whisk till combined. Continue change of state for a further 1-2 minutes till the sauce simply barely begins to simmer round the edges of the pan (avoid belongings it return to a boil) and thickens. Then take away from heat and put aside.
- Spread half the sliced potatoes in an excellent layer on the lowest of the pan. prime equally with half the bechamel. (I sometimes strain out all of the onions and add them here too.) Then sprinkle equally with one cup of the sliced cheese, and every one of the Parmesan cheese. prime equally with the remaining sliced potatoes, the opposite half the bechamel, and also the remaining one cup of cheese.
- Cover the pan with tin foil and bake for half-hour. The sauce ought to be nice and bubbly round the edges.
- Then take away the foil and bake uncovered for 25-30 minutes, or till the potatoes ar medium through.
- Transfer the pan to a cooling rack, and sprinkle with the remaining teaspoon of thyme and additional Parmesan. Serve warm.
*I advocate not shopping for pre-grated cheese for this instruction, since it’ll not soften yet. Instead, it’s best if you buy a block of cheese and shred it yourself simply before baking. Over the years, I actually have conjointly experimented with a range of various cheeses here. whereas I like the flavour of sharp cheese, mozzarella, gouda, fontina and Gruyere work nice too! (Or be at liberty to use a mix!)