Season lamb with lemon juice, olive oil, garlic powder, sumac, salt, pepper, and onion puree. For best results, let marinate for at least 4 hours
Once ready to cook lamb, ln a stovetop pan, over medium heat, add 1 tsp olive oil. Cook lamb 3-5 minutes per side.
Then make your yogurt dip. For the dip, grate cucumber and sprinkle with salt and let sit in a strainer. Meanwhile, in a mixing bowl, mix Greek yogurt, olive oil, lemon juice, salt, pepper, garlic powder and dried mint; mix. Then add in strained cucumber.
On a large plate, add arugula, mint, and toss in olive oil/lemon juice dressing. Add lamb, lemon slices, toasted walnuts, and cherry peppers. Serve yogurt dip as desired on the side.