Place the thinly slice sirloin into a large mixing bowl and pull-apart the thin meat slice into bite-sized pieces
Put Sugar (2.5 teaspoons) in and thoroughly rub it into the meat. Set it aside and let it marinate for 20 minutes.
After 20 minutes: Put in Pureed onion (2 teaspoons), Minced Garlic (1 teaspoon), Soy Sauce (6 teaspoon), Black Pepper (6 cracks) into the mixing bowl with the meat. Give it a thorough mix.
Then drop in 1 teaspoon of Sesame Oil. Give it one more mix with your hands
Let meat rest again for 10 minutes
Slice-up onions, shiitake mushrooms, spring onions and mild red pepper. Place vegetables into the mixing bowl with the marinated beef
Drop in another 2 teaspoons of Sesame Oil into the mix. Thoroughly mix it in one final time.
Get a non-stick frying pan up to a medium-high heat
Quickly cook the meat (no need to put additional oil on the frying pan - we used plenty of sesame oil)