Mix the patties: Put the lamb mince in a bowl with the za'atar, salt and pepper. Mix with clean hands. Divide into 4 equal pieces, roll into balls and press gently into thick patties.
Heat the pan: Place a large non-stick frying pan over a high heat until smoking hot. Drizzle with a little oil.
Sear the burgers: Cook for 4 minutes without moving. Flip and cook for another 4 minutes on the other side.
Make the salsa: While the burgers cook, slice the red onion finely. Chop the preserved lemon peel (discard the flesh). Toss with the coriander leaves and squeeze the lemon juice over the top.
Make the harissa yoghurt: Stir the harissa paste into the natural yoghurt.
Add the peppers: Cut the roasted peppers into strips and lay them over the burgers in the pan. Remove from the heat.
Build the burger: Spread harissa yoghurt on the bun lids. Stir the shredded lettuce into the remaining yoghurt and spoon onto the bottom halves. Place the burgers on top, spoon over the onion and preserved lemon salsa, and close.
