This was originally a side dish, but as it’s very rich and there are just two of us, I now make it as a complete meal, like I do Mac ‘n Cheese.
4-6 rashers smoky bacon (for meat eaters)
OR 1 tsp smoked paprika (for a meat free version)
2 medium potatoes
3-4 leeks with a long white portion
(Oil/butter for the meat free version)
Chop the bacon and cook it in a large pan. Meanwhile, scrub and thinly slice the potatoes. Thoroughly rinse and slice the leeks, white and pale green parts only, being sure there’s no sand between layers.
Remove the bacon from the pan (or heat oil and or butter) and cook the potatoes and leeks until soft, about 20 minutes. Try not to break up the leek slices. (If not using bacon, sprinkle smoked paprika on the veg.)
While that cooks, make a cheddar cheese sauce.
3 tbsp butter
3 tbsp flour
2 cups milk or cream (or half of each)
1 egg yolk, beaten (optional)
2 cups sharp cheddar (or smoked Gouda?), shredded
Melt the butter with the flour to make a roux. Cook for about 2 minutes, or until it no longer smells like raw flour. Remove from heat for a minute, then stir in the milk until it’s smooth. Put it back on the burner and cook for a few minutes. (If you use the beaten egg yolk to stabilize and thicken, add it carefully now) when the sauce is thickened, stir in the cheese until it’s melted.
Heat oven to 350F. In a lightly greased casserole: Layer potato/leek mix, bacon (if you’re using it) and sauce with sauce being the top layer. Bake uncovered for 30-45 minutes until bubbly and lightly brown around the edges.