Using a long, thin serrated knife, slice the sour dough bread into 1 inch slices down to the bottom of the bread. Be careful not to slice through the bottom crust - we want the bread to stay intact.
Turn the bread and make slices down to the bottom of the bread again to make about 1 inch cubes. Again, slice just to the bottom, but not through it!
In a small bowl, mix together the melted vegan butter, minced garlic, and minced fresh parsley.
Using a pastry brush, liberally brush the vegan garlic butter between all the slices of bread.
Transfer the melty vegan cheese to a reusable decorating piping bag or a large gallon ziplock with corner snipped off and pipe the mozzarella cheese in between all the slices of bread. See photos for reference.
Finally, wrap loaf in tin foil and place on baking sheet. Bake for 15-20 minutes wrapped in foil. Then bake an additional 10 minutes without foil.
Top with fresh parsley and serve immediately.
Notes
There is no substitute for the tapioca flour in the melty vegan cheese recipe.
If you find you have leftover cheese, it makes a good grilled cheese or use it for anything you'd use mozzarella in.