How to make thai food: Sweet and Sour Pork, Chicken, Shrimp

1/2 lb of pork, diced
You can also use chicken or shrimp
1/2 large onion
2 tomatoes
1 cucumber
1 clove minced garlic
2 tbls fish sauce (or salt to taste)
1 teaspoon vinegar
1 teaspoon tomato paste
1 tbls corn starch
3 tbls vegetable oil

What you do

Heat the oil in a pan or wok over high flame and fry the garlic in oil until brown. Put in the pork (or chicken or shrimp). When this is cooked add the onion and stir for 1 minute. Add cucumber, fish sauce, soy sauce and pour in one cup of water. As soon as this boils put in the corn starch that has been mixed with a little cold water. Then add vinegar and tomato paste. When the sauce thickens then your dish is ready.