McCormick Mississippi Roast Instant Pot Seasoning Mix 1.25 oz Envelope. Mississippi Instant Pot Roast is the perfect dish for the pressure cooker or slow cooker. Made with just 5 ingredients- including McCormick Instant Pot Mississippi Roast Seasoning Mix- it’s on the table and ready for your crew in an hour. Chuck roast comes out of the Instant Pot tender and flavorful thanks to a generous sprinkle of Mississippi Roast Seasoning Mix butter and pepperoncini peppers. Ideal for busy weeknights it’s also easy to whip up this meal in the slow cooker. Prepare slow cooker roast per the convenient on-pack directions (cook eight hours on low four hours on high). Seasoning mix is made with McCormick spices. No artificial flavors. This McCormick Mississippi Roast Instant Pot Seasoning Mix is in a Plastic packet that is 1.25 ounces. Store this shelf-stable item at an ambient temperature.