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.
In a skillet over medium heat, add pork belly and cook, stirring occasionally, until lightly browned and crisp. Remove from pan and drain on paper towels.
Peel shrimp, leaving tail intact. Reserve shrimp heads. In a pot over medium heat, bring 1 cup water to a boil. Add shrimp and cook for about 1 to 2 minutes or until color changes. With a slotted spoon, remove shrimp from pot and set aside. Reserve liquid.
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.