Grilled yellowtail with charred tomato-nopal salsa

Grill ripe tomatoes, green chilies and knob onions, and nopal paddles drizzled with a little olive oil.

For the marinade, crush and finely chop about six garlic cloves and combine in a bowl with olive oil, the juice of key limes, sea salt and a little black pepper; stir the yellowtail in it and leave to marinate while making the salsa.

Cut the tops off the grilled chilies, scrape the seeds, skin them or not, and chop with the tomatoes, skinned or not; slice the onion knobs into rings and chop the softened nopales.

Season the salsa with Mexican oregano crushed between the palms and sea salt.

Grill the well-oiled fish without flipping too early; turn when it moves freely and is crusted, and cook until a little less resilient and flaking under firm pressure.

Serve the fish with the grilled salsa as tostadas, topped with crunchy chicharron.