Heat a little oil in a wok over high heat. Season the shrimp with salt and pepper. Sear just until they change color, then set aside.
Lower the heat to medium. Add the pork and a little water. Let the water evaporate, then brown the pork, adding oil if needed. Season lightly with salt.
Add the ginger and cook until lightly browned. Add the garlic and onion; cook until softened. Stir in the shrimp paste and sauté briefly.
Add 1½ cans of coconut milk. Simmer until the pork is tender, then add the squash and chilies. Simmer gently for 15–20 minutes, until the squash is tender. Add more coconut milk or water as needed.
Add the sitaw and shrimp. Cover and cook for 2–3 minutes, or until the beans are tender and the shrimp are fully cooked. Taste and season with fish sauce, salt, or pepper.
Notes
Kalabasa: I used kabocha; its skin softens when cooked. Butternut squash also works.
Sitaw: Substitute green beans.
Pork and shrimp: Use both or just one, or substitute chicken, tofu, dried fish, or smoked fish.
Coconut milk: Use full-fat canned coconut milk. Start with 1½ cans and add more as needed.
Shrimp paste: Raw or sautéed works. Taste before adding salt or fish sauce.