Grilled Chicken Sandwich with Apricot Sauce

Season chicken breasts with salt and pepper. Drizzle with olive oil and grill until cooked all the way through. Wrap in plastic wrap and efrigerate until needed. Combine equal parts apricot preserves, Dijon mustard, and mayonnaise. Add cayenne to taste. Refrigerate until needed. To assemble, spread apricot sauce on two slices of bread. Add chicken breast, baby spinach, and red onion slices. Serve cold or drizzle with olive oil and brown on a panini grill. Serve with kettle-cooked potato chips.