Thinly slice the flank steak against the grain into bite-sized strips and season with sea salt and black pepper.
In a small bowl, whisk together the tamari, honey, grated ginger, minced garlic, and arrowroot powder to create the stir-fry sauce.
Heat the avocado oil in a large skillet or wok over medium-high heat until shimmering.
Add the beef strips in a single layer and sear for 2-3 minutes until browned and caramelized, then remove from the pan and set aside.
Add the broccoli florets to the same pan with a splash of water, covering with a lid for 2 minutes to steam until tender-crisp.
Return the beef to the pan, pour the sauce over the mixture, and toss constantly for 1 minute until the glaze thickens and coats everything.
Drizzle with sesame oil and garnish with sesame seeds before serving hot.