In a non-stick pan over medium heat, sauté thinly sliced onions in coconut oil. Get them slightly caramelized, which should take between 12 to 15 minutes. Then add mushrooms and continue to cook for another 8 to 10 minutes. Once all the water is out of the mushrooms and they're soft and brown, divide the mixture in half in the pan and create portions that are about the length and width of the baguettes. Turn the heat down to low or right off and break up the jack cheese wedge into chunks and place them on top of the mushrooms and onions in an even fashion. Place a lid on the pan and let it melt while you prep the bread and any sides for your sandwich.
Slice the baguettes in half and lightly toast. Spread vegan butter on either side. Then once the cheese looks melted and gooey, lift the mushroom mixture with melted cheese with a spatula and place directly on the bottom slice of each baguette. Sprinkle with coconut bacon, place the top slice of baguette on top and cut in half.
Notes
Look for the Daiya Jack Style Wedge used in this recipe here.