Place the melted butter, fish sauce, tamari sauce, vinegar and seasonings into a large bowl. Stir well to coat.
Use a knife or pizza cutter to cut the protein sparing bread into small 1 centimeter square pieces. Place the small protein sparing bread pieces and nuts into the butter mixture and stir to coat well.
Bake 45 minutes, stirring every 20 minutes. Remove from oven and allow to cool completely so the protein sparing bread bites crisp up. If the protein bread cubes are not crispy after cooling, place back into the oven for 15 minutes.