Wash the meat, dab dry and cut into cubes of about 2 cm. Peel garlic and chop finely. Mix meat with juice from ½ lemon, 2 tbsp. oil, spices and half of garlic. Marinate covered in the fridge for about 2 hours.
For the dip, wash, clean and coarsely grate the zucchini. Salt and let it stand for about 10 minutes, drain off the liquid. Mix zucchini, rest garlic, 2 tbsp. oil, yoghurt and juice from ½ lemon. Season to taste with salt, pepper and sugar. Keep cold.
Soak wooden skewers in water. Roast oregano and sesame seeds in a pan without fat. Let them cool down briefly, crush them with some sea salt in a mortar. Drain the meat and place it on the wooden skewers. Grill on the hot grill for about 15 minutes. Serve with dip, sesame salt and, if desired, some red onion strips.