Mexican Ground Beef with Potatoes

Name: Mexican Ground Beef with Potatoes
Cuisine: Mexican, Latin American, American
Ingredients: 1 tbsp vegetable oil; 1 small onion, finely chopped; 3 cloves garlic, minced; 1 lb ground beef; 2 medium potatoes, peeled and diced; 1 large tomato, chopped; 1/2 cup tomato sauce; 1/2 cup beef broth or water; 1/2 tsp ground cumin; 1/2 tsp ground cinnamon (optional, for a traditional touch); 1/2 cup frozen peas (optional); Salt and black pepper, to taste; Fresh cilantro, chopped, for garnish