On the Season Two premiere of MASTERCHEF's "Junior Edition," America's first-ever MASTERCHEF JUNIOR, Alexander Weiss, returns to the kitchen as a special guest. Alexander presents the mystery box challenge, and the 16 junior home cooks will be tasked with preparing impressive dishes using the special guest's favorite ingredients, including pork chop, pork tenderloin, green apples, hazelnuts, Brussel sprouts, filo dough, fingerling potatoes, wild rice, whole grain mustard and artichoke. The winner of the challenge will have a significant advantage and select which of the judges' favorite proteins the remaining contestants will prepare in the elimination round. Later, the 12 junior home cooks with the best dishes will advance in the competition.