Toss all the ingredients together in a bowl. Portion using a scale to ½ oz. wt, or use a #40 scoop. Place on a cookie sheet and roast at 325 degrees for about 10 minutes, until medium rare. Let cool, then transfer to the refrigerator until needed. Warm the meatballs in beef stock until hot and cooked completely. Serve with salsa de arbol and garnish with julienne red cabbage.
Salsa de Arbol
Roast the tomatoes, tomatillos, garlic cloves, and white onion under the broiler until cooked through and charred on the outside. Meanwhile, toast the arbol chilies in a sauté pan until fragrant and toasty, then rehydrate in hot water for 20 minutes. Stem and transfer to the blender along with the roasted ingredients and all other ingredients. Blend until the chilies are chopped. Season and transfer to a bowl and store refrigerated.