I had half each of bitter melon, long eggplant, red and green bell peppers and decided to make a sweet-sour-spicy dish. It can be served with warm jasmine rice or even simple roti or naan. The picture shows it served with a small portion of chicken breast per the Other Half's request.
I salted the bitter melon for 10 minutes; rinsed and patted dry; then par-cooked in the microwave.
For the sweet-sour-spicy sauce:
2 tbsp sambal oelek
1 tbsp soy sauce
1 teaspoon tamarind paste
1 tbsp mirin
Stir the sauce ingredients. Adjust to taste as preferred. Heat some oil in a caste iron skillet, add the veggies, saute; add the sauce stir well and cook till desired doneness of the veggies. I like them crisp-tender.