• Finely chop enough garlic to measure 2 teaspoons.
• Grate or peel and finely chop the ginger.
• Thinly slice the mushrooms.
• Remove the stem, ribs, and seeds from the bell pepper; thinly slice the pepper.
• Trim the root ends from the scallions; thinly slice the scallions on the diagonal.
• In a bowl, combine the teriyaki sauce base with the arrowroot powder and as much sambal oelek as you like. Stir to blend.

In a pot over medium heat, warm 2 tablespoons oil until hot but not smoking. Add half the garlic and cook until fragrant, about 1 minute. Add the cauliflower "rice", season with salt, and cook, stirring occasionally, until just softened, 5 to 6 minutes. Cover partially to keep warm.
While the cauliflower cooks, make the stir-fry.

• Pat the steak strips dry with a paper towel; season generously with salt and pepper.

In a pan over medium-high heat, warm 1 tablespoon oil until hot but not smoking. Add the steak strips and cook, stirring, until browned but not yet cooked through, 2 to 3 minutes. Transfer to a plate.

Add 1 tablespoon oil to the pan and warm over medium-high heat until hot but not smoking. Add the ginger and the remaining garlic and cook, stirring, until fragrant, about 1 minute. Add the mushrooms and bell pepper, season with salt and pepper, and cook, stirring often, until they start to soften, 2 to 3 minutes. Stir in the teriyaki sauce and cook for 1 minute.
Return the steak to the pan and cook, stirring to coat with the sauce, until the steak is cooked through, 1 to 2 minutes. Remove the pan from the heat and stir in the scallions.

Transfer the cauliflower rice to individual plates. Top with the stir-fry and serve.