Thinly slice the red peppers, mince the garlic and ginger, slice the spring onions, and set aside.
Thinly slice the beef against the grain. Place the Marinade ingredients into a bowl with the beef and massage through.
Lightly toast the szechuan peppercorns for a few seconds, and then pop into a mortar and crush slightly.
Combine the sauce in a ramekin.
Get the wok to smoking hot, cover the bottom of the wok with oil, place the beef in and seer on both sides. Set aside.
Add a little more vegetable oil and add the red peppers for a few seconds.
Next the ginger and garlic, for 10-20 seconds. Followed by the Szechuan peppercorns.
Place the beef back into the wok and warm it through.
Add the sauce in, and toss through.
Top with the spring onions and sesame seeds.
