In a large mixing bowl, combine the ground beef, ground pork, and ground lamb (if using).
Add the minced garlic, baking soda, black pepper, dried thyme, dried rosemary, paprika, salt, and ground cumin. Mix well to combine all the ingredients.
Gradually add the sparkling water while mixing to achieve a smooth and slightly sticky texture.
Stir in the vegetable oil and vinegar. Continue to mix until the mixture is well combined and slightly elastic.
Cover the bowl with plastic wrap and refrigerate for at least 2 hours, or overnight for best results.
Preheat your grill to medium-high heat.
Take small portions of the mixture and shape them into small sausages, about 4-5 inches long and 1 inch thick.
Grill the mititei on the preheated grill, turning occasionally, for about 10-12 minutes, or until they are well-browned and cooked through.
Remove the mititei from the grill and let them rest for a few minutes before serving.
Enjoy your meal!