Step 1

Thinly slice meat against the grain and place in a large bowl. Season with salt, black pepper, and onion powder and add en egg. Make sure that all beef is coated with the egg and add corn starch.

Step 2

Add vegetable oil to a frying pan and allow it to warm over medium-high heat. Place the beef strips in the heated oil in a single layer, do not overcrowd the pan - fry in batches if needed! Stir fry for about 4 minutes per side, until golden brown.

Step 3

Remove the strips of beef from the pan with tongs or a slotted spoon and place on a paper towel to drain any excess oil. Repeat until all beef is fried.

Step 4

Make the spicy sauce: add sliced onions to the pan. Add an additional tablespoon of oil if needed. Saute onions until they've softened and become fragrant, about 3 minutes. Then add sliced red chillies, grated ginger, and diced garlic. Continue to cook for 2 minutes.

Step 5

Add rice vinegar, soy sauce, tomato pasta, sweet chilli sauce, and sugar. Whisk together until all ingredients are full incorporated and a sauce forms. Bring to a light boil and remove from heat. Add beef into the pan and toss together. Serve over rice or or with noodles and garnish with sesame seeds, sliced spring onions, and additional chilli flakes.