Slice the flank steak against the grain into thin, bite-sized strips.
Season the beef strips evenly with sea salt and black pepper.
Heat the toasted sesame oil in a large skillet or wok over medium-high heat until shimmering.
Add the beef to the hot skillet and sear until browned and caramelized, about 2-3 minutes, then remove and set aside.
In the same skillet, add the broccoli florets, sliced red bell pepper, fresh ginger, and garlic.
Sauté the vegetables for 4-5 minutes until they are vibrant and crisp-tender.
Return the beef to the skillet and pour in the coconut aminos, tossing for 1 minute to glaze the ingredients.
Prepare the cauliflower rice in a separate pan over medium heat for 3 minutes until softened.
Divide the cauliflower rice into bowls, top with the beef stir-fry, and garnish with sesame seeds.