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. You'll want to put this sauce on everything.
Pulse the garlic and cilantro, until finely chopped in a small blender. Add cream and cream cheese as well as lime juice, salt, and pepper. Blend until creamy and adjust seasonings to taste.
For the Bistek:
Marinate steak and onions in coconut aminos, salt, and lemon for at least 30 min.
Drain and reserve marinade.
Sear the ribeye in a cast iron pan to desired doneness. Remove to a covered plate and let the steak rest. While the steak rests, add onions to the same pan and saute until soft and beginning to brown. Add in reserved marinade and cook till little liquid remains, about 5 more minutes. Remove from heat.
Off heat, add in sliced, rested steak.
Serve steak and onions with sliced tomatoes, fresh cilantro, cilantro garlic sauce, and lemon slices.