In order to aviod cross-contamination, we take many steps to ensure the quality of our gluten-free pizzas. The first step is in the morning when the prep cook comes in, they setup an isolated work area in the cooler for building the gluten-free pizzas. When an order comes back, the cook making the pizza discards their gloves and apron, washes their hands and puts on a clean apron and new pair of gloves. When the pizza is made it is fired into a separate oven designated for gluten-free pizzas. When the pizza comes out the cook again changes gloves and washes their hands and delivers the pizza to the table themselves so the server who has been running plates with the other pizza dough and sandwiches will never come in contact with the pizza.
I am not an employee of mellow mushroom. But I can tell you they are amazing so I would maybe just call them and bet they would explain how they prevent cross contamination. That's what we have always done when we have a question about food handling before we visit the restaurant.
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