Thinly slice the flank steak against the grain into bite-sized strips for maximum tenderness.
In a small bowl, whisk together the coconut aminos, toasted sesame oil, minced ginger, and minced garlic to create the glaze.
Heat the avocado oil in a large skillet or wok over high heat until it is shimmering.
Add the beef strips in a single layer, seasoning with sea salt and black pepper, and sear for 2 minutes until browned and caramelized.
Remove the beef from the pan and add the broccoli florets with a tablespoon of water, covering the pan for 2 minutes to steam-soften the florets while keeping them bright green.
Return the beef to the pan, pour in the prepared glaze and red pepper flakes, and toss for 1 minute until the sauce thickens and coats every piece.
In a separate pan or the microwave, lightly steam the cauliflower rice until tender but not mushy.
Serve the beef and broccoli over the cauliflower rice and garnish with toasted sesame seeds for a final crunch.