To make these Brussels Sprouts ahead, slightly undercook them the day before—they should still be a little crunchy and slightly raw looking in the very center. Reheat (which will finish the cooking) just before serving in a large skillet on the stove or in a buttered, covered baking dish in the oven.
By the way, sautéed Brussels sprouts are clearly not just for Thanksgiving. They are one of my go-to vegetable dishes all fall and winter long. When I make just one container on a busy weeknight, I simply sauté them in olive oil and season with a squeeze of lemon juice, salt and pepper.