Slice the flank steak into thin strips against the grain to ensure maximum tenderness.
In a small bowl, whisk together the coconut aminos, smoked paprika, and arrowroot powder until smooth.
Heat the toasted sesame oil in a large skillet or wok over medium-high heat until shimmering.
Add the beef strips to the pan in a single layer, seasoning with sea salt and black pepper, and sear for 2 minutes until browned.
Toss in the broccoli florets and sliced red bell pepper, sautéing for 3-4 minutes until the vegetables are crisp-tender.
Stir in the minced garlic and grated ginger, cooking for 30 seconds until fragrant.
Pour the sauce mixture over the beef and vegetables, tossing constantly for 1 minute until the sauce thickens and becomes glossy.
Serve immediately while hot and steaming.