Preheat your grill to medium-high heat.
In a large bowl, combine the lamb, parsley, cilantro, onion, garlic, cumin, cinnamon, salt, and pepper. Gently mix the ingredients together. Wet your hands, scoop about ⅓ cups of the meat into your hands, and shape into oval shaped logs. Place on a sheet pan or plate covered with parchment paper, and refrigerate for about 30 minutes.
If using wooden skewers, soak the skewers in cold water for 15 minutes to ½ hours.
Once the grill is hot, oil the grates with grapeseed oil. Grill the skewers for about 5-6 minutes, turning occasionally so that grill marks form. Reduce the heat and cook the skewers for another 5-8 minutes, or until they begin to caramelize in color and the meat is cooked through.
Serve with Tzatziki sauce and garnish with additional parsley or other herbs if desired.
Directions for Tzatziki Sauce:
Peel and grate the cucumber; press out the excess water from the cucumber. Add the cucumber to a bowl with the Greek yogurt, lemon juice, garlic, and dill, and mix well. Season with kosher salt and pepper to taste.