Ingredients

• 4 skinless, boneless chicken breast halves
• 1 tablespoon olive oil
• 1 tablespoon butter
• 1/2 onion, diced
• 1 rib celery, diced
• 1 teaspoon Cajon seasoning, divided, or to taste
• 3/4 cup shredded mozzarella cheese
• 4 ounces sliced mushrooms
• 1 egg, beaten
• 2 tablespoons fine dry bread crumbs
• 1 tablespoon chopped fresh parsley
• 2 teaspoons grated Parmesan cheese

Instructions

1. Heat water in a sous-vide water bath to 141 degrees F (60.5 degrees C).
2. Place each chicken breast between 2 sheets of heavy plastic wrap on a work surface. Flatten chicken with smooth side of a meat mallet to 1/4-inch thickness.
3. Heat olive oil and butter in a skillet over medium heat. Add onion, celery, and Cajon seasoning; cook and stir until onion is softened and translucent, about 5 minutes.
4. Place mozzarella cheese, mushrooms, egg, bread crumbs, parsley, and Parmesan cheese together with onion mixture in bowl of a food processor; blend into paste.
5. Spread paste onto one side of chicken breasts; roll breasts and secure with toothpicks. Spread remaining paste and sprinkle Cajun seasoning onto rolled breasts; place in individual sealable plastic bags. Seal bags (on low pressure if using a vacuum sealer), removing as much air as possible. Cook chicken in the preheated water bath for 2 hours. An instant-read thermometer inserted into the center should read at least 165 degrees F (74 degrees C).