1. Add your soy sauce, pineapple juice, apple cider vinegar, garlic and ginger root to a deep 8x8" baking dish (or anything you have to marinade your steak) and mix to combine. Add your steak slices to the marinade. Marinade for 1-2 hours, up to overnight.

2. Once the steak is marinated, take it out of the marinade and pat it dry with paper towels. Throw the marinade away.

3. Heat the grapeseed oil in a large skillet over medium-high heat. When the oil is hot, add the skirt steak strips, spreading them out so they're not touching. Cook, without touching the steak until the undersides are lightly browned, about 90 seconds.
 

4. Flip the steak strips and cook until both sides are browned and the steak is cooked to medium-rare, about 90 seconds more. Take the steak strips out of the pan and set them aside on a plate.
 

5. Turn the heat on the skillet down to medium-low and add the chicken stock, garlic, ginger, and scallion whites.

As the chicken stock simmers, scrape the bottom of the pan with a spoon or spatula, to release any browned steak bits stuck to the pan. Cook until the stock is almost evaporated and the garlic and ginger are fragrant about 45 seconds.
 

6. Add the raw cauliflower rice, tamari, and mustard greens. Cook, stirring occasionally until the cauliflower is tender and the mustard greens are bright green, about 4 minutes. If the liquid evaporates and things start to stick, add a splash of water.
 

7. When the cauliflower is tender, add the cooked steak strips and the sliced scallion greens, toss everything together, and serve immediately.