Spread Crostini Butter evenly onto the outside of both slices of sourdough.
Evenly distribute sliced cheddar onto the inside of both slices of sourdough.
Evenly distribute pizza cheese onto the bottom slice of sourdough leaving a 1/2" border.
Gently press the cheese to keep it contained inside the sandwich.
Place the second slice of buttered sourdough on top of the cheese with the butter side facing up.
Wrap in plastic wrap, and food corral sandwich bag (if applicable). Label each sandwich with corresponding day label, or internal dating system.
Transfer sandwiches to clean food storage containers. Cover, label, date and store refrigerated.
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