In a medium mixing bowl, whisk together soy sauce, lime juice, canola oil, honey, adobo seasoning and cumin. Pour 1/4-cup marinade over peppers and onions; toss to combine, refrigerate. Pour remaining marinade into a zip-top plastic bag and add flank steak; marinate in refrigerator 2 hours, flipping half way through.

Place oven rack on top slot, set oven to broil/high and preheat. The rack should be positioned 3 to 4 inches from heating element. If needed, use a cast iron skillet under sheet pan to elevate it closer to heating element.

Line a sheet pan with aluminum foil, spray with non-stick spray. Remove flank from marinade, blot dry with paper towels. Drain peppers and onions of excess liquid. Place flank in center of tray and spray top with non-stick spray. Spread peppers and onions in even layer on tray, surrounding the beef.

Broil 8 to 12 minutes (or until well browned) with flank directly under broiler. Remove sheet pan from oven, use tongs to flip flank, toss the veggies around on the pan. Return to oven; broil 3 more minutes.

Remove sheet pan from oven, transfer flank to cutting board, lightly tent with foil. Using tongs, move veggies around on pan to arrange in a single layer, return to broiler for an additional 3 minutes.

Rest flank steak 5 to 10 minutes before slicing thinly across grain. Wrap tortillas in damp paper towel, place on plate and microwave 1 minute on high. Toss beef with peppers and onions; serve with warm tortillas.