Slice the pork thin. Freeze it for 15 minutes first if you can—it makes clean, thin slices easier. Cut against the grain into bite-size strips.

Whisk the sauce. In a bowl, combine tamari, rice vinegar, sesame oil, sweetener, fish sauce, and stock. If using xanthan gum, sprinkle it in while whisking vigorously to avoid clumps. Set aside.

Prep the veggies. Keep pieces small and even: thin bell pepper strips, bite-size broccoli florets, trimmed snow peas, and sliced green onions (separate whites from greens).

Heat the pan. Place a large skillet or wok over medium-high heat. Add 1 tablespoon oil and swirl to coat until shimmering.

Sear the pork in batches. Add half the pork in a single layer. Season lightly with salt and pepper. Cook 1–2 minutes per side until just cooked through and slightly browned. Transfer to a plate and repeat with remaining pork, adding a splash more oil if needed.

Stir-fry the aromatics. Add remaining oil, then toss in garlic, ginger, and green onion whites. Stir for 30 seconds until fragrant—don’t let them burn.

Cook the vegetables. Add broccoli first and stir-fry 2–3 minutes. Add bell pepper and snow peas and cook another 2 minutes. You want crisp-tender, not soft.

Combine and sauce. Return the pork to the pan with any juices. Stir the sauce again and pour it in. Toss everything 1–2 minutes until coated and glossy. If too thick, splash in a bit more stock; if too thin, simmer briefly to reduce.

Finish and serve. Sprinkle with red pepper flakes and green onion tops. Garnish with sesame seeds. Serve over cauliflower rice or enjoy as is.