Begin by preparing the ingredients. Mix the ground lamb with the cumin powder and add salt and pepper to taste. Knead the meat firmly and shape into round meatballs the size of a walnut. Peel the onion and garlic, mince the onion finely and chop the garlic cloves into small pieces. Use a spiralizer to create long strands of courgettes and set this courgetti aside.
Heat the olive oil in a braising pan over medium-high heat. Brown the lamb meatballs on all sides. Add the minced onion and chopped garlic and cook briefly until the onion is translucent. Pour the diced tomatoes into the pan with the meat and stir well. Lower the heat and simmer the sauce for ten minutes until the meatballs are cooked through.
After the cooking time, add the courgette strands to the hot tomato sauce. Gently fold the courgetti through the sauce and meatballs and heat for exactly two more minutes. The courgette strands should only be heated through so they retain their texture and don't become too soft.
Divide the warm courgetti with tomato sauce and lamb meatballs among the plates. Serve immediately.