Thinly slice the flank steak against the grain into bite-sized strips and season with sea salt and black pepper.
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 minutes until browned, then remove from the pan and set aside.
In the same pan, add the broccoli florets, sliced red bell pepper, and edamame with a splash of water to steam-sauté for 3 minutes.
Stir in the minced garlic and grated ginger, cooking for 30 seconds until the aroma is fragrant and bold.
Return the beef to the pan and pour in the tamari and toasted sesame oil, tossing everything together for 1 minute to glaze.
Plate the stir-fry immediately and garnish with sesame seeds for a delicate toasted finish.