Sweet and Sour Stir Fry

* I have made this stir fry many times. I really enjoy it!

1 pound boneless pork or chicken breast , cut into strips
2 tablespoons vegetable oil
1 clove garlic, minced or a bit of dried garlic
1 large onion, sliced finely
4 carrots, sliced
1 red pepper, sliced
* you can add other vegetables also if you desire eg. bean sprouts, or sugarsnap peas
In large non-stick frying pan, place the oil and sliced pork or chicken breast. Stir fry till done and golden brown. Add all the vegetables and continue to stir fry for another 10 minutes.
Now Add:
1/2 teaspoon black pepper
2 tablespoons soya sauce
3 tablespoons brown sugar
2 tablespoons vinegar
1 cup water
1 OXO beef cube or 1 tablespoon OXO liquid

Place 1 tablespoon cornstarch in small bowl. Add a little water and stir it. Add to stir fry to thicken as needed. Cook the Stir Fry just a bit longer to thicken.
Serve on hot rice!