M&S Mexican Style Achiote Beef Mexican style tender British beef coated in a spicy and smoke marinade. Perfect in a soft tortilla with guacamole or add to cheesy nachos and so much more. Oven cooks in 35 minutes or microwave in 8 minutes. Serves 2. Why not try... shredded spicy, smoky beef with warmed soft flour tortillas and a dollop of zesty guacamole, topped with naked pickled slaw.