1. Cook rice noodles according to package instructions. If using traditional Pancit Malabon rice noodles, soak it overnight.
2. Combine noodles, sauce, cabbage, crushed chicharon, and tinapa flakes. Toss, then transfer to a plate.
3. Top it with shrimps, pork, egg slices, spring onions, and fried garlic. Serve with sliced calamansi.

For Pancit Malabon Sauce:

1. Dissolve 1 cup of flour in 1 cup of water. Set aside.
2. To cook the shrimp stock coarsely chop reserved shrimp heads. In a pot over medium heat, combine shrimp heads and 6 cups water (including the reserved liquid from boiling the shrimp). Bring to a boil, skimming any foam that rises to top. Lower heat and simmer for about 10 minutes to extract flavor. Using a fine mesh strainer, strain liquid and discard shrimp solids.
3. Heat achuete oil in a pan. Sautèe garlic.
4. Add shrimp stock. Bring to boil. Pour in water with dissolved flour. Add salt and pepper to taste. Add fish sauce. Set aside.

For the Toppings:

1. In a small pot over medium heat, bring about 2 cups water to a boil. Add cabbage and cook for about 30 to 35 seconds or until tender yet crisp. With a slotted spoon, remove from pot and submerge into a bowl of iced water. Drain well and set aside.
2. In a pan over medium heat, add pork belly and cook, stirring occasionally, until lightly browned and crisp. Remove from pan and drain on paper towels.
3. In a pot over medium heat, bring 1 cup of water to a boil. Add shrimp (with heads removed)  and cook for about 1 to 2 minutes or until color changes. With a slotted spoon, remove shrimp from pot and set aside. Peel when it cools down. Reserve liquid.
4. In a pan over medium heat, add 1 tablespoon oil. Add tinapa flakes and cook, stirring regularly, for about 1 to 2 minutes or until lightly browned and heated through. Remove from pan and set aside.