Best Potato Gratin Recipe

Grease a 9x13x2 inch casserole dish (glass or ceramic preferred) with 1 tablespoon butter, set aside. I smoosh the butter in the dish using a paper towel to schmear evenly. *or use a large gratin dish, at least 2 quarts, do not use an 8x8 pan as your gratin will overflow into your oven.

Bring milk, cream, garlic, rosemary, thyme, salt and pepper to a low simmer. Cooking on low for 30 minutes. Strain out herbs and garlic into a bowl, discarding the herbs and garlic. Reserve infused cream mixture.

While your cream mixture simmers, slice the potatoes 1/8 inch thick -- if you've never used a mandoline slicer give it a try, your slices will be even and uniform and be done lickity-split! Place sliced potatoes in a bowl of cold water until ready to assemble, then drain and pat dry.

Arrange potatoes in rows, overlapping slightly; seasoning each layer with salt and pepper. Toss together the gruyere and sharp cheddar cheese. Sprinkle a handful of cheese over potatoes and pour 1/2 cup cream mixture over the potatoes. Repeat steps twice, (or many times as you have ingredients) finish by pouring on an remaining cream mixture. Dot with 1 tablespoon butter; cover with foil and bake.

Bake in preheated 375°F (190°C) oven for 45 minutes; then remove foil and continue baking, uncovered for an additional 45 minutes, until golden brown and bubbly and potatoes are fork tender (insert fork into potatoes; they should yield to gentle pressure). Remove from oven and let rest 15 minutes before serving, this gives the sauce time to set up so every slice holds together.