This is a flavor bomb! The steak has umami from the reduced coconut aminos and the cilantro garlic sauce is bright, tangy, and assertive, cutting through the richness of the steak nicely.
Marinate steak in coconut aminos, salt, and lemon for at least 30 minutes.
While the steak marinates, prepare the sauce. Combine all ingredients un a high power blender and blend until completely smooth. Adjust seasoning to taste, adding more salt and a bit of coconut aminos if it is more sour than you like. Set aside.
Heat a nonstick pan over medium-high heat. Add the beef along with the marinade and cook until browned on all sides cooked to your liking, about 7 minutes for medium rare (125ºF).
Serve over a bed of lettuce with the sauce drizzled over top.