Slice the flank steak into even 1/2 inch wide strips. You can do this with a knife or simply cut into strips with kitchen scissors. Add the beef strips to a medium-sized mixing bowl. Sprinkle the xanthan gum evenly over the beef strips. Use your hands to toss the steak pieces and xanthan gum together, lightly coating the beef all over with the powder.
Heat the olive oil in a large skillet or wok over a medium/high heat. Add the coated steak strips. Stir fry the beef strips in the hot oil for 4-5 minutes until well browned all over.
While the beef is browning, you can prepare the sauce. Add the tamari sauce, maple-flavored syrup, apple cider vinegar, lime juice, sesame oil, garlic powder, ground ginger, Chinese five-spice, coriander, chili flakes and black pepper to a small bowl. Whisk together well to combine. Please feel free to adjust the spices to personal taste, adding more or less as required. Be sure to adjust your macros to account for any changes.
Drizzle the Szechuan inspired sauce into the skillet, coating the beef strips. Stir well to combine. Let the sauce bubble and thicken, coating the beef all over. Continue to stir fry for just a few more minutes until the sauce has reduced right down to a glaze, coating the steak strips evenly. Serve the beef hot with your preferred toppings and sides.