Asian Steak Roll Ups

Name: Asian Steak Roll-Ups
Ingredients: 1 c. low-sodium soy sauce; 3/4 c. brown sugar; Juice of 2 limes; 2 garlic cloves, minced; 1 tbsp. Dijon mustard; 1/4 tsp. cayenne pepper; 1 lb. skirt steak, cut into thin 2-long strips; 2 tsp. extra-virgin olive oil; 1 large red bell pepper, thinly sliced; 1 large zucchini, sliced into thin strips; 1 large summer squash, sliced into thin strips; Sesame seeds, for garnish; Sliced scallions, for garnish