Step 1: Prepare the Broth - Blanch the pork bones and trotters in boiling water for 5 minutes to remove impurities. Rinse under cold water and then return to pot with fresh water, onion, garlic, ginger, and leeks. Simmer for 6-8 hours, skimming as necessary.

Step 2: Make the Chashu Pork - Roll pork belly tightly and tie with kitchen twine. Combine soy sauce, mirin, sake, and sugar in a pot, heat gently, add pork belly, and simmer for 2-3 hours. Allow to cool before slicing.

Step 3: Prepare Black Garlic Oil - Heat neutral oil in a small saucepan over low heat. Add black garlic and crushed garlic, cook for about 10 minutes until fragrant. Blend with sesame oil and soy sauce until smooth.

Step 4: Make Soft-Boiled Eggs - Boil eggs for 6.5 minutes, move to an ice bath immediately. Once cooled, peel and marinate in leftover braising liquid for at least 30 minutes.

Step 5: Cook the Noodles - Prepare noodles according to package instructions, usually a quick 2-3 minutes for fresh noodles. Drain and rinse under cold water.

Step 6: Assemble the Ramen Bowl - Ladle broth into bowls, add noodles, top with chashu pork, marinated eggs, and desired toppings. Drizzle with black garlic oil before serving.