Preheat oven to 350 degrees. Place bread crumbs on cookie sheet and place in oven on center rack. Toss bread crumbs every couple of minutes, for about 5 to 7 minutes. Set aside to cool. Heat 1 tablespoon of the olive oil in a saute pan over medium-low heat. Add onions, cumin, and season with salt and pepper. Saute onions until transparent, stirring occasionally about 5 to 7 minutes. Remove from heat, set aside and cool. Place sliced bread in a bowl and add milk to cover. Soak until bread becomes soft, pressing on bread to absorb liquid. Drain excess milk. In a mixing bowl, combine ground meats and Sauteed onion with garlic, parsley, egg and milk-soaked bread. Work mixture with your hands until ingredients are well combined. Add toasted bread crumbs a bit at a time, thoroughly mixing with each addition. The meat mixutre should be moist to the touch, but not wet. Form meat into small balls about 1-inch in diameter. Set a large, heavy bottomed saute pan over medium heat and add the remaining 3 tablespoons of olive oil. Heat until oil is hot, but not smoking. Cook meatballs, turning, until all sides are browned, about 5 minutes. Move meatballs from heat and drain on paper towels.;
Place a sauce pot over low heat and add olive oil to warm. Add onions and saute, stirring, until translucent, about 8 to 10 minutes. Add garlic and cook for 1 minute. Add cumin and oregano and stir to combine. Season with salt and pepper and add red wine. Reduce liquid by half. Crush tomatoes with your hands and add to sauce along with tomato juice. Bring sauce to a boil, then reduce heat to a simmer. Skim sauce to remove any impurities from the top. Add chicken stock, stir to combine, and add meatballs. Cook 25 to 30 minutes, uncovered.
To serve, plate 4 meatballs per person, sprinkled with additional cumin, fresh parsley and drizzle with extra virgin olive oil.