Green Bean Casserole - Ellie Krieger

Ingredients

• 1 ½ pounds thin fresh string beans or haricot vert, trimmed
• 2 tablespoons olive oil, plus more for brushing the pan
• 1 pound button mushrooms, sliced
• 6 large cloves of garlic, minced (about 2 tablespoons)
• 1 tablespoon chopped fresh thyme
• 3 cups milk (low-fat, whole or unsweetened oat milk)
• 3 tablespoons all purpose flour
• 1/3 cup plus 2 tablespoons freshly grated Parmesan cheese
• ½ cup finely chopped fresh flat-leaf parsley
• ¼ teaspoon ground nutmeg
• ¾ teaspoon salt
• ½ teaspoon freshly ground black pepper
• ½ cup crispy onions or shallots, store bought or homemade (see note)