Slice the flank steak against the grain into thin strips to ensure maximum tenderness.
Season the beef strips evenly with the sea salt and black pepper.
In a small glass bowl, whisk together the coconut aminos, grated ginger, and toasted sesame oil to create the stir-fry sauce.
Heat the avocado oil in a large skillet or wok over high heat until it begins to shimmer.
Add the beef strips in a single layer and sear without moving for 1-2 minutes until deeply browned, then flip and cook for 1 more minute before removing from the pan.
Add the broccoli florets to the same pan with two tablespoons of water, immediately covering with a lid to steam for 3 minutes until vibrant green and tender-crisp.
Remove the lid, return the beef to the pan, and add the minced garlic, sautéing for 30 seconds until fragrant.
Pour the prepared sauce over the beef and broccoli, tossing constantly for 1 minute until the sauce thickens and glazes the ingredients.
Transfer to a plate and garnish with the sesame seeds before serving hot.