Cook up to 15-in. Pizzas with the Blackstone Pizza Oven Conversion Kit. This kit converts your 22-in. Blackstone Griddle into the pizza oven of your dreams. This pizza oven features our patented 2stone technology. One stone on the bottom and one stone on top creates an even cook in less than 5 minutes. With a built-in thermometer and a heat retaining front door, you’ll be creating delicious pizzas in no time.