Slice the flank steak against the grain into thin, bite-sized strips.
Mince the garlic clove and finely grate the fresh ginger.
Heat a large skillet or wok over medium-high heat and add the toasted sesame oil.
Add the beef strips to the skillet, seasoning with sea salt and black pepper, and sear for 2-3 minutes until browned.
Transfer the beef to a plate and set it aside.
In the same skillet, add the broccoli florets and water; cover with a lid to steam for 2 minutes until tender-crisp.
Remove the lid and stir in the minced garlic and grated ginger, sautéing for 30 seconds until fragrant.
Return the beef and any accumulated juices to the pan, then pour in the coconut aminos.
Toss everything together for 1 minute until the sauce coats the beef and broccoli evenly.
Garnish with sesame seeds and serve immediately.