Fill a large pot of water and add beef shank and salt. Bring to a boil over high heat and cook for 10 minutes. Remove meat from pot, rinse in water and cut into thick pieces. Disregard liquid
Smash garlic and chop carrots, tomatoes, ginger, onion and green onions into 2" pieces
Pour oil in a large frying pan or wok and sear beef with salt and pepper until brown on all sides. Then add in carrots, tomato, ginger, onion and green onion. Stir fry for 5-10 minutes
Add whole cloves, star anise, cinnamon, bay leaves, and dried chilis. Stir fry until fragrant and veggies have soften down. (Additional 5-10 minutes)
Add soy sauce, chili oil, spicy bean paste and Chinese black vinegar. Stir until becomes thick.
Slowly mix in beef broth or water. Bring to a boil, set heat to low, cover and let simmer for 1-4 hours depending on the level of flavor you desire (The longer you cook, the more flavorful the broth will become)
Blanch boc choy and prepare your noodles according to packaging. To assemble the bowl, add your noodles, boc choy, sliced tomato and beef. Add broth and garnish with green onions and chilis