Prepare the Gyros Meat

1. Preheat oven to 325F. In a food processor, process the onion for about 15 seconds until it is minced.  Pour the minced onion into a tea towel, wrap and squeeze the liquid from the minced onion, draining into the sink.  Squeeze until very little of the liquid remains. Return the onion to the processor.  Add the lamb, garlic, marjoram, rosemary, salt and pepper.  Process until the meat mixture is a fine paste.  This takes about a minute.  You will likely need to scrape down the sides once or twice during the process.
2. Scrape the lamb mixture into a loaf pan.  Press the mixture all the way to the sides of the pan. This will help the meat form the best shape for slicing. Place the loaf pan into a 9x13x2 baking pan.  Put the baking pan into the oven, then pour hot water (boiling or nearly boiling) into the baking pan until it is about half-way up the side of the loaf pan, being careful the water doesn’t go into the loaf pan of meat.
3. Bake until meat reaches 165-170F,  about 60-75 minutes.  Drain off any fat from the meat.  Place the loaf pan on a cooling rack.  Take a brick that has been wrapped tightly in aluminum foil, and place it over the surface of the meat for 15-20 minutes. Remove meat from the pan, thinly slice, then serve on the salad, topped with the remaining dressing and a dollop of Tzatziki Sauce.

Prepare the Tzatziki Sauce

1. Mix together the yogurt, chopped cucumber, minced garlic, oil, vinegar, salt and mint leaves.  Keep refrigerated until serving time.

Grill the Salad

1. Heat your grill to Med-Med High.  Place the salad ingredients on separate skewers:  2 skewers for cherry tomatoes, 2 skewers of Halloumi cheese, 2 skewers of onion wedges.
2. Make the marinade:  In a jar with a lid, add the dijon mustard, marjoram, salt, pepper and vinegar.  Shake to mix.  Add the olive oil, cover and shake vigorously to emulsify.
3. Pour half of the marinade over the skewers, reserving half for dressing the salad.
4. When grill is hot, grill skewers until tomatoes are charred (1-2 minutes per side), cheese begins to brown on the outside (2 mins/side) and onions begin to char (3-4 mins/side).  Remove from grill.  If you would like to char the lettuce, separate the leaves and place on the grill about 15-30 seconds.

Assemble the Salad

1. Arrange or combine the lettuce, onions, cheese, cherry tomatoes, cucumbers, olives, and pepperoncinis.  Drizzle the remaining marinade/dressing over the salad.  Top with slices of gyro meat.  Add a dollop of tzatziki sauce.
2. Serve with wedges of pita bread and more tzatziki sauce.