Wash the string beans thoroughly and cut off the ends. Cut the sitaw into approximately 2- to 3-inch pieces. Slice the pork belly into thin strips or small bite-sized pieces. Mince the garlic, slice the onion, and chop the chili pepper if using.

Heat the cooking oil in a large skillet or wok over medium-low heat. Add the sliced pork belly and cook until the pork changes color and becomes lightly golden brown. Allow some of the pork fat to render, which will add more flavor to the dish.

3Sauté the aromatics

Add the sliced onion and sauté briefly until it starts to soften. Add the minced garlic and continue cooking until fragrant. Be careful not to burn the garlic.

Add the cut string beans to the skillet. Stir well to combine the sitaw with the pork and aromatics. Cook for about 2 to 3 minutes while stirring occasionally.

Pour in the soy sauce and oyster sauce. Stir thoroughly so the seasonings are evenly distributed among the pork and string beans.

Pour in 1/2 cup of water and stir. Cover the skillet and lower the heat. Let the dish simmer for about 5 minutes, or until the pork is cooked through and the string beans reach your preferred tenderness.

For slightly crisp sitaw, avoid overcooking. If you prefer softer vegetables, simmer for another minute or two.

Taste the dish and add salt and ground black pepper as needed. Since soy sauce and oyster sauce are already salty, add salt gradually. If you want a spicy version, add the chopped red chili pepper during the final few minutes of cooking.

Transfer to a serving dish and serve hot with steamed rice.