In measuring cup place all sauce ingredients. Mix well. Pour about ⅓ of mixture over the flank steak and let sit 15-30 minutes. Reserve rest of sauce for serving.
Barley and Vegetables
In medium saucepan place barley and water. Heat to boil over medium-high heat. The barley may start to foam when it starts to boil. Turn down to simmer. Start checking the barley after 25 minutes, then every 5 minutes after that until done. The barley should be soft, but still a bit al dente. When barley is done. Cover. Set aside.
In medium frypan heat oil. Sauté bell pepper and onion on medium low heat, until soft and beginning to get colour, about 10 minutes.
Beef
In heavy bottomed cast iron pan over medium heat. Add 2 tbsp canola oil. Place flank steak in pan and fry until golden brown (about 5 minutes). Turn to the other side and cook about 10 minutes more. Cook until the internal temperature is about 145°F (62°C) . Let rest 10 minutes before slicing.
To serve
Place barley in bowl, top with sautéed vegetables and meat slices.