Cut and measure all foods before heating pan and have ready to toss into mixture.
Heat oil in wok over medium heat. The pan is ready when you place a few drops of water in the pan and it pops and sizzles on the pan. If it evaporates quickly, then the pan is too hot.
Add raw chicken and cook until browned BEFORE you add vegetables, but if using pre-cooked chicken, add chicken AFTER vegetables are cooked.
Put carrots, celery, and yellow onion into wok, stirring and cooking until golden and cooked to your preferred tenderness.
Add green onions and walnuts, heating through.
Place lemon zest (and pre-cooked chicken, if you did not use raw chicken) in pan and toss quickly until warmed through.
Turn off heat.
Add coconut aminos or soy sauce (or don’t if you prefer it without a soy flavor – you might add salt instead).
Place in serving bowl, then drizzle the juice from the two lemons over the mixture and ground pepper to taste. Toss vigorously.
Serve over cauliflower rice, brown rice, or quinoa.