Classic Homemade Green Bean Casserole

This recipe takes the traditional Thanksgiving side dish and elevates it by replacing canned soup with a homemade cream sauce and fresh sautéed mushrooms. It requires just eight ingredients and takes a little over an hour to prepare. The process begins by blanching the green beans in salted water and shocking them in ice water to lock in their bright color and crisp texture. Aromatics like onions, garlic, and fresh mushrooms are cooked in butter, then combined with a simple from-scratch cream sauce made from butter, flour, and milk before baking. To save time on busy holidays, the casserole can be assembled up to four days in advance without the fried onions and stored in the refrigerator. The fried onions should only be added during the final minutes of baking to ensure they retain their signature crunch.