Chop mushrooms.
Heat 2 tablespoons olive oil and add mushrooms, salt and pepper. Cook for about 15 minutes on medium heat until caramelized
Put goat cheese in a bowl and softenwith a fork or spoon. Add 2 tablespoons of milk one a time until you create a thick goat cheese cream.
Add cooked mushrooms to the goat cheese.
Toast bread and drizzle olive oil on the outside of each slice.
Spread 1-2 teaspoons mustard on the inside of each slice of bread.
Spread 2 tablespoons goat cheese and mushroom mix on each slice of bread.
Add 1 slice of gouda cheese on each slice and add 3 slices of green apple.
Put the 2 slices of bread together to form a sandwich.
Heat a non-stick skillet on medium heat and brown sandwich on both sides until golden, crunchy and gouda cheese is melted. About 3-4 minutes per slice