To make scalloped potatoes from scratch, its best to make an herb and garlic infused cream that is heavily seasoned. The potatoes are thinly sliced peel on or peel off. Then layered in a casserole dish raw. The pan should not be much deeper than 3 inches to ensure even cooking. The infused cream is drizzled over each layer and then repeated until the dish has many layers of potatoes and cream. The potatoes are covered and cooked low and slow (325-350 F) until the potatoes fully cook and their starch thickens the cream into a velvety smooth sauce this can take up to 90 minutes. To cut down on the cooking time the potatoes can be par-cooked in water or in a steamer, though if this method is used a small amount of corn starch or potato starch should be added to the cream since the potatoes will have lost a good amount of starch during the par cooking process. The cream penetrates the potatoes seasoning them with herbs, garlic, salt and pepper. For the last few minutes of cooking the potatoes should be uncovered so the oven and caramelized the top of the casserole. The potatoes should cool for 5-10 minutes before serving. This ensures that they soak up any of the cream and have the ultimate texture.