Thinly slice 1/2 red onion and transfer to a small bowl. Cover with 1/2 tsp salt, 1/2 tsp sumac, the juice of 1 lemon and 1/2 tbsp honey. Toss until evenly coated, then set aside.
Heat 3 tbsp olive oil in a large pan on medium-high heat. Break 400g ground lamb into large pieces and place in the hot pan, leaving a little space between each. Let cook undisturbed until golden brown. Using a spatula, break the lamb into smaller pieces and season with 2 tsp salt, 1 tsp paprika, 1 tsp cumin, 1 tsp garlic powder, 1 tsp onion powder and 1 tsp dry thyme. Mix to incorporate, then continue cooking on medium-high heat until dark brown and crispy, about 20 minutes, stirring occasionally to prevent burning.
Cut 2-3 round pitas into bite-sized triangle pieces. Transfer to the air fryer, cover in oil (about 1 tbsp) and toss to coat. Cook at 375°F for 8-10 minutes, or until golden brown. If you don't have an air fryer, bake in the oven at 375°F until golden brown and crispy, about 10-15 minutes.
By now the lamb should be deeply browned and caramelized. Remove from heat and set aside. Assemble your bowls with a generous scoop of hummus, topped with spiced lamb, sumac red onions and mint leaves. Serve with your favourite pickled things, or some roasted vegetables and feta.
