Pulse together ⅓ red onion, 4-6 cloves garlic, ⅓ cup pistachios, and a large handful fresh parsley in a food processor.
Add 2 lbs ground beef (or mixture of beef/lamb) to a bowl and top it with the processed marinade.
Add a couple pinches of salt, 1 tbsp smoked paprika, 1 tsp cumin, 2 tbsp sumac, ground pepper, and mix well.
Cover and let it marinate for 30 mins, ideally 2-4 hours.
Roll the mixture into logs, patties, or your preferred shape and grill or pan fry on medium-high heat.
For the yogurt sauce, mix ¾ cup thick Greek yogurt with salt, pepper, juice of ½ small lemon, 1-2 minced/grated garlic cloves, 2 tbsp fresh dill, and 1 shredded Persian cucumber.
Adjust the yogurt sauce to taste.
Cut halloumi cheese into thin slices and grill until golden brown on both sides on medium heat.
Assemble by adding 2 tbsp of the yogurt sauce, 2-3 kaftas, 2 slices of halloumi, thinly diced red onion, cucumber, fresh parsley, and sumac over your pita of choice.
