First, prepare the sumac marinated onions: Thinly slice 1 red onion. In a deli container, toss the sliced onion with the juice of ¼ lemon, 1-2 tbsp sumac, and a pinch of salt. Let it sit while you make the tacos; it gets better as it sits and lasts in the fridge for 2 weeks. Next, make the lamb smash tacos: In a bowl, mix 1 lb ground lamb with 1 tsp cumin, 1 tsp coriander, ¼ tsp aleppo chili or cayenne, and 2 tsp salt until evenly combined. Place a flour tortilla on a cutting board. Scoop a portion of lamb (about the size of a large golf ball) onto it and gently press it into a thin, even layer, spreading it almost all the way to the edges. Repeat with the remaining 6-8 tortillas. To freeze for later: Stack the tortillas meat-side up with square sheets of parchment paper between each one. Slide the stack into a zip-top freezer bag, seal, and freeze flat. They keep beautifully for about a month and cook straight from frozen. To cook: Pull one taco from the freezer and let it thaw for 5–10 minutes while your pan heats. Heat a skillet over medium-high heat with a little olive oil. Place the taco meat-side down and cook for about 5 minutes, until deeply golden and cooked through. Flip and cook the tortilla side for 1–2 minutes, just until warm and slightly crisp. Serve with labneh or Greek yogurt (or cottage cheese), fresh cilantro, chickpeas (roasted or raw), and the sumac & lemon marinated onions.
