SUPER EASY METHOD
1. Mix the mayonnaise, mustard, salt and pepper in a bowl. Spread onto the top and sides of the Premium Chicken Breast (Boneless Skinless) (not underside).
2. Sprinkle panko over the chicken, using your other hand to press the breadcrumbs onto the side of the chicken. Spray with oil.
QUICK DREDGE METHOD
1. Whisk egg and flour. Dip chicken into egg mixture, then into the panko breadcrumbs. Transfer to tray, spray with oil.
BAKING
1. Bake for 25 to 30 minutes, or until golden brown and just cooked through. Remove toothpicks, serve with the Dijon Cream Sauce.
DIJON CREAM SAUCE
1. Melt butter over medium heat in a small saucepan. Add flour and cook for 1 minute.
2. Add half the milk and whisk until the flour mixture is blended in.
3. Add remaining milk, mustard and cheese. Cook for 3 minutes, whisking constantly, until thickened. It will thicken as it cools.
Remove from heat, add salt and pepper to taste. Serve with chicken.
Source: https://www.recipetineats.com/chicken-cordon-bleu-easy-fancy/