Thinly slice the flank steak against the grain into bite-sized strips and season evenly with sea salt and black pepper.
In a small glass bowl, whisk together the coconut aminos, minced fresh ginger, and minced garlic to create the stir-fry sauce.
Heat the extra virgin olive oil in a large skillet or wok over medium-high heat until the oil is shimmering.
Add the beef strips to the hot pan in a single layer and sear for about 2 minutes until browned, then remove the beef and set it aside.
In the same pan, add the broccoli florets and sliced red bell pepper, sautéing for 3-4 minutes until they are tender-crisp.
While the vegetables cook, lightly steam the riced cauliflower in a separate small pan or microwave until heated through and soft.
Return the seared beef to the skillet, pour in the prepared sauce mixture and the toasted sesame oil, and toss everything together for 1 minute to glaze.
Portion the cauliflower rice into a bowl, top with the beef and vegetable stir-fry, and garnish with sesame seeds before serving.