Preheat a sandwich press.
On one side of each of the bread pieces, spread butter evenly.
On the non-buttered side of one piece of toast, begin to layer the ingredients. Turkey, Avocado, Tomato, basil, mozzarella, salt and pepper.
Top with the remaining piece of sourdough, butter side facing up.
Place the sandwich on the sandwich press and gently press down the lid. Toast for 3-5 minutes or until the cheese has melted and the sandwich is golden.