Skittles is coming out with a new flavor this summer. In honor of National Mustard Day on August 5th, Skittles and French’s are collabing with mustard flavored Skittles. Fans will get to taste the new flavor at French's "Mustard Mobile" that will be making stops in Atlanta, Washington D.C. and New York City next week. You’ll have a chance to win a free fun-sized packet of the French’s Mustard Skittles through three pop-ups and an online sweepstakes while supplies last. Enter to win a pack here.