Stir the ingredients for the marinade together in a measuring cup of mixing bowl. Slice the steak into thin strips - about ¼ inch thick and 2 inches long. Place the steak in a plastic bag and pour in the marinade. Allow steak to marinate for at least 1 hour (up to 24).

Stir together the ingredients for the sauce in a mixing bowl or measuring cup (note that many of the ingredients for the sauce and marinade overlap, so you may consider making the sauce at the same time you make the marinade).

When you’re ready to cook the steak, heat a large skillet to high heat and add 2 tablespoons of avocado oil (or high temperature cooking oil of choice). Add the steak and cook, stirring occasionally, until the steak gets a golden-brown crust and begins to stick to the skillet.

Transfer the beef to a plate and add the vegetables to the skillet to sauté them (you can add more avocado oil if need be). Sauté, stirring occasionally, until onion begins to turn translucent and vegetables reach desired done-ness, about 3 to 5 minutes.

Transfer the beef back to the skillet, along with the sauce. Stir well and bring everything to a boil. Cook, stirring constantly, until everything is well-coated in thick sauce and the beef is cooked through, about 3 to 5 minutes.

Serve Szechuan Beef over choice of steamed rice or cauliflower rice.