An Iron Chef quietly opened a restaurant concept at the Philadelphia International Airport. Chef-restaurateur Michael D. Symon can be seen on the Food Network on Iron Chef America and The Best Thing I Ever Ate, and ABC's The Chew. The James Beard Award winner slowly expanded outside of the Midwest in the past few years, including the Philadelphia region; he opened restaurant Angeline in the Borgata Hotel Casino & Spa earlier this year. Symon took an under-the-radar approach with his latest expansion…