Cut roast pork into 1/2 by 2 inch pieces. Chinese style roast pork can be obtained in Chinatown.
Cut vegetables into bite sized pieces. Other vegetables that can be used.
are long beans instead of green beans, and squash or chayote.
Heat oil in a large heavy pot over medium high heat.
Saute ginger, garlic and tomato in oil until garlic is transluscent.
Add roast pork and stir-fry for two to three minutes until pork is heated through.
Add in vegetables except bitter melon. Add fish sauce and tomato paste. Reduce heat to medium. Partially cover pot and simmer stirring occasionally until vegetables are almost tender. Add water if necessary to prevent sticking.
Add shrimp and continue cooking until shrimp are pink and done.
Adjust seasoning by adding salt or additional fish sauce.
Add in bitter melon. Cook until bitter melon is tender. Do not stir; shake pot instead. Do not over cook or damage bitter melon Bitter melon can be omitted if you do not like the bitter taste.