Pizza Hut said Tuesday that it is testing a round pizza box and plant-based Italian sausage topping, made by the MorningStar Farms Incogmeato brand in Phoenix. Pizza Hut is part of the Yum Brands Inc. /zigman2/quotes/209029767/composite YUM +0.53% portfolio, and Morningstar Farms is part of the Kellogg Co. /zigman2/quotes/209631250/composite K +0.35% roster of brands. The round pizza box uses less overall packaging and is compostable. Following the test, Pizza Hut will look to roll out the box "in the near future." Pizza Hut, which partnered with a sustainability company called Zume to create the round box, says it was two years in the making. The Garden Specialty Pizza will not only be topped with Incogmeato, but also onions, peppers, and mushrooms. This is the second item to come from the Pizza Hut/Kellogg partnership, following the launch last month of the Stuffed Cheez-It pizza. The Garden Specialty Pizza served in the round box will be available in-store only priced at $10 with proceeds going to a local sustainability organization, Arizona Forward. Yum Brands stock has gained 22.2% for the year to date, Kellogg stock is up 9.6%, and the S&P 500 index /zigman2/quotes/210599714/realtime SPX +0.24% has rallied nearly 20% for the period.