Slice the flank steak against the grain into thin strips and season with sea salt and black pepper.
In a small bowl, whisk together coconut aminos, toasted sesame oil, fresh ginger, garlic, arrowroot powder, and 1 tbsp water.
Heat a large skillet over medium-high heat and coat with avocado oil.
Add the beef strips in a single layer and sear until browned, about 2-3 minutes, then remove from the pan and set aside.
Add the broccoli florets and sliced carrots to the same pan with the remaining 1 tbsp water, covering for 2 minutes to steam until tender-crisp.
Return the beef to the pan and pour the prepared sauce over the mixture, tossing for 1 minute until the sauce thickens and coats the ingredients.
Remove from heat and garnish with sesame seeds before serving.