How to prepare your Crispy Beef Strips:

1. Thaw out the beef strips in the fridge overnight.
2. In a clean deep pan, pour your choice of cooking oil to around 1-2 inches high, or just enough for deep frying. Heat the oil over high heat until the temperature reaches 170 C, for around 15-18 minutes. Note: If without a thermometer, dip the end of a wooden spoon or chopstick into oil. If the oil steadily bubbles around the utensil, it should be ready. If bubbling is too vigorous, oil is too hot.
3. In a clean bowl, prepare an egg wash by combining 1 whole egg with ¼ cup of water.
4. Coat beef strips with egg wash and evenly dredge with 200gm (roughly 2 cups) of cornstarch. Shake off excess cornstarch.
5. Gradually and slowly add the beef strips into the hot oil. Make sure the beef strips are loose and not stuck together.
6. Deep fry the beef until golden brown and crispy, for around 7-8 minutes. If needed, fry in batches to avoid overcrowding the pan. If beef pieces clump together, break apart with tongs.
7. Remove from pan, shake off excess oil, and transfer to a bowl lined with a paper towel. Let it cool for around 30 seconds to let the crust crisp up. 
8. Heat the sauce in a pan over medium heat (for around 3 minutes), or in the microwave just until warmed through (for around 45 seconds).
9. Take the paper towel out and pour sauce over the fried beef. Carefully toss until evenly coated.
10. Transfer to a plate and serve hot.