Chicken and Rice Casserole with Cream of Mushroom Soup

Name: Chicken and Rice Casserole with Cream of Mushroom Soup
Ingredients: 5 tablespoons unsalted butter; 8 ounces sliced cremini mushrooms; 1 small onion, diced; 2 cloves garlic, chopped; 1 1/4 cups wild rice blend; One 10.5-ounce can condensed cream of mushroom soup; 4 cups low-sodium chicken broth; 2 teaspoons Dijon mustard; 2 teaspoons soy sauce; 1 teaspoon kosher salt; 1/2 teaspoon freshly ground black pepper; 1 bay leaf; 4 fresh thyme sprigs; 1/2 cup grated Parmesan; 1 sleeve butter crackers (32 crackers), crushed; 3 cups loosely packed baby spinach; 2 cups shredded rotisserie chicken (skin and bones removed)