Creamy Chicken and Rice Casserole

INGREDIENTS

• 3 tablespoons olive oil, divided
• 4 cups sliced mixed mushrooms (10 ounces)
• 2 shallots, minced
• Salt and pepper
• 2 tablespoons all-purpose flour
• 2 1/4 cups chicken broth
• 4 cups shredded chicken, from a small rotisserie chicken
• 2 cups cooked rice (white or brown)
• 1/2 cup frozen peas
• 1/2 cup fresh parsley, chopped
• 1/2 cup reduced-fat sour cream
• 1 cup fresh breadcrumbs