DO-AHEAD TIP: Marinate beef strips overnight or for at least 4 hours (see recipe). Prepare broccoli.
Lightly season beef strips with salt and pepper then place them in a large zipper-topped plastic bag; add coco-aminos, garlic, and olive oil.
Seal the bag and turn to coat steak strips; seal the bag and refrigerate overnight or for at least 4 hours. Heat a large skillet or wok over medium-high heat; add marinated steak strips (adding additional oil if necessary); stir-fry for about 10 minutes or until browned on the outside.
Add broccoli florets; stir fry with beef strips for 1 minute; serve.