Place 1 Large Flank Steak in Large Ziploc bag and add enough Maker's Mark to cover when laying on it’s side (about 2 cups).
Add the remaining ingredients and mix well with your fingers.
Marinate overnight, flipping the bag occasionally.
Grill steak to medium rare over charcoal.
Take remaining marinade and bring to a boil, cook well and season to taste (with more chili flakes and salt & pepper).
You can also add a little sugar and more Maker's Mark. When you get it to how you like it, add cornstarch to thicken, simmer and constantly stir until you get the desired consistency you’d like.
Notes
To cut Flank steak, take your knife down the path to the wide end, lay your knife almost flat on top and slice perpendicular to the grain. Thin slices are best. Serve with sauce.