Slice beef into 2"x3/4" slices and sprinkle with salt and pepper
Brown beef in coconut oil on high heat (in batches if necessary), transfer to a bowl, and set aside.
Reduce heat to medium and add mushrooms to the pan with additional oil if needed. Spread the mushrooms into a single layer and allow them to sear on one side, then flip them over to sear on the other side (this is optional but gives the dish some extra flavor).
When the Mushrooms are browned add the garlic powder, pink salt, onion powder and red pepper flakes. cook for 1-2 minutes until the spices bloom and brown a little bit - be careful not to burn the spices, it can happen pretty quick.
Mix the beef bullion cube with boiling water to make about 2 cups of broth and add it to the pan with the mushrooms and spices. Bring to a boil and add the liquid aminos or soy sauce. You may want to taste the broth before adding the full amount of aminos to make sure it doesn’t get too salty - start with a 1/2 teaspoon and work up.
Once the broth comes to a boil, let it cook for a few minutes until it reduces by about a third, then add the Xanthan Gum, the broccoli, and the beef. Toss everything together and cook for a few minutes more until the sauce thickens and the broccoli is tender.