https://chefsavvy.com/scalloped-potatoes/#recipe

2 1/2 pounds russet potatoes or yukon gold, sliced thin 1/4 cup butter 1 medium onion, small dice 4 cloves garlic, minced 1/4 cup all-purpose flour 2 cups milk 1 cup chicken stock 1 tsp dried mustard 1/4 teaspoon dried thyme 1/4 teaspoon paprika 2 cups sharp cheddar cheese, shredded and separted salt & pepper to taste parsley for garnish

Preheat oven to 375f. Grease a 9X13 pan.
Melt butter in a large saucepan.
Saute onions, until slightly browned.
Add garlic, cook for less than a minute.
Add in flour, cook for a minute.
Slowly whisk in milk and hot chicken stock.
Add mustard, thyme and paprika.
Add in 2 cups of the cheese. Reserving 1/2 cup for topping.
Layer 1/3 of the potatoes into baking pan.
Top with some sauce.
Repeat til sauce is on top and top with cheese.
Cover with foil and bake for 35 minutes. Remove foil and bake additional 45 minutes, or til tender.
Garnish with parsley. Eat.