Cut up vegetables and set aside in large mixing bowl.
Whisk eggs and add to vegetables. Stir until well mixed.
Prepare gravy: In a fry pan, saute mushrooms in butter. Then add the other gravy ingredients (except xanthun gum). Stir up and add xanthun gum slowly (gradually, while stirring). Simmer and stir occasionally until gravy thickens (may add more xanthun gum to thicken).
While gravy is simmering, cook egg and vegetable mixture in a large fry pan by scooping a large spoonful into pan, like you're making pancakes. Cook until bottom is browned and top isn't runny, then flip to brown other side.
Serve egg foo young topped with the gravy mixture and enjoy!
Serve up with cauli rice or cauli fried rice! If you like your brown gravy sweet, just add a little sweetener like Swerve.