In the meantime, its time for a gadget plug. A mandoline slicer. Oh heavens. Best invention ever. I got mine for $19 off amazon. Its amazing.
So unless you want to manually slice 4 potatoes and a onion into 1/4 inch slices, INVEST.
Anyway. This dish is crack. Ooey gooey. Carby. Comforting. A good holiday or sunday meal dish. The potatoes still have enough bite in them that they aren't mush. Its just a great dish.
You could add some ham or bacon and make a meal out of it!
Cheddar and Feta Au Gratin Potatoes
4 medium Russet potatoes, sliced into 1/4 inch slices
1 onion, sliced into as thin of slices as possible
4 garlic cloves, sliced (or minced, if desired. I like chunks)
3 tbsp butter
3 tbsp flour
2 cups milk
2 cups cheddar cheese
4oz feta crumbles
salt and pepper to taste.
Prep your potatoes, onion, and garlic.
Place a single layer of potato sliced on the bottom of a greased casserole pan.
Melt the butter in a saucepan on medium. Add the flour and cook 3 minutes, stirring often. Add the milk. Whisk until combined. Once hot, but not boiling, add the cheddar. Whisk until combined. Add salt and pepper. Move off heat.
Ladle a ladle or two of sauce on potatoes. Add a layer of potatoes, then some onion, garlic, and feta. And then another overlapping layer of potatoes. Spoon a bit more sauce on top. Repeat until done. Ending with sauce and a little feta.
Cover with tin foil and bake at 375 for 1 and 1/2 hours.
Let sit 5-10 minutes, then serve.