Start by finely chopping the onion and mincing the garlic. Set them aside.
Take your slice of white bread and soak it in a little water for a few minutes. Once soft, squeeze out the excess water and crumble it into a mixing bowl.
In the mixing bowl, add the ground beef, soaked bread, chopped onion, minced garlic, egg, and all the spices: salt, smoked paprika, paprika, oregano, cumin, chili powder, pepper, ground coriander, nutmeg, and tomato puree.
Using your hands, mix everything together until just combined. Be careful not to overmix, as this can make the meatballs tough.
With your hands, shape the mixture into small meatballs, about 1 to 1.5 inches in diameter. Place them on a baking sheet lined with parchment paper.
You can either bake the meatballs in a preheated oven at 400°F (200°C) for about 20-25 minutes or pan-fry them in a skillet with vegetable oil over medium heat until browned and cooked through.
Once cooked, serve your Mexican Meatballs with your favorite dipping sauce, over rice, or in tortillas for a tasty taco night!