Mongolian Pork Tenderloin

Mongolian Pork Tenderloin

Ingredients:
1/2 kilo pork tenderloin
2 tbsp. soy sauce
1/4 tsp. pepper
3 tbsp. cornstarch
2 tbsp. cooking oil

1 medium onion
2 cloves garlic
1 tbsp. ginger
few pieces of spring onions
1 small red bell pepper

Mongolian sauce:
1 tbsp. soy sauce
1 tbsp. oyster sauce
1 tbsp. chili-garlic sauce
1 tbsp. brown sugar
1/2 tbsp. oil
1 cup water
2 tsp. cornstarch