Tender Juicy Beef and Onion Stir Fry

—-Ingredients(4 servings)—
6.7 oz/190 g onion
4 stalks of green onion
1/4 tsp salt
1/4 tsp sugar

4 cloves of garlic
16.9 oz/480 g beef
2 tsp soy sauce
2 1/4 tsp dark soy sauce
3/4 tsp oyster sauce
3/4 tsp sugar
1 1/2 tsp baking soda
4 1/2 tsp corn starch

3 tsp oil
1 1/2 tsp sesame oil

3 tbsp oil for cooking
3 tsp dark soy sauce
1 1/2 tsp oyster sauce
1 1/2 tbsp cooking wine
1/3 cup water
Black pepper