Heat oil in medium saucepan over medium heat. Add onion, bay leaves, and garlic then sauté until tender, about 5 minutes. Add the tomato, 1/2 tsp of salt, and 2 cups of water cover the saucepan and let it simmer for about 10 minutes and remove from heat. In a seperate pot pour the 3 quarts of water or broth on med heat. In a blender carefully pour the warm sauce but remove the 2 bay leaves and blend until smooth ( cover your blender lid and hold with a kitchen towel, in case anything spills). Pour your blended sauce into the pot and continue to cook on medium heat.
Preparing the meatballs:
In a large bowl place your ground beef, rice, 1tsp of salt, 1/4 tsp pepper, raw egg, 1/4 tsp of cumin, 1/2 cup of finely chopped cilantro, (use your hands) mix everything well together.Form 1-inch meatballs, you can make them smaller or bigger if you like, the bigger the meatball the longer it will take to cook. Bring your pot to low heat and add meat balls one at a time. Add Chayote, carrots, and the mint leaves cover and let it cook on low-medium heat.
Cover and let simmer for about 30 mintues until meatballs are cooked through. Add potatoes towards the end of the cooking and add any needed salt to taste.
Serving suggestions:
Laddle warm in a bowl, and garnish with cilantro. Add side of warm corn tortillas. You can add salsa or finely chopped Serrano peppers.