3tablespoonscanola oil or other high smoke point oil, divided
1green bell pepper, cut into strips
1red bell pepper, cut into strips
1orange or yellow bell pepper, cut into strips
1/4cupchopped cilantro or parsley
Juice of a lime
Salt and freshly ground black pepper
8 to 12Flour tortillas
Mix all the dry ingredients for the marinade together, then rub them into the flank steak Put this in a bag or plastic container in the fridge for up to a day, and no less than 2 hours. If you are only going to let it marinate 2 hours, add the lime juice right away. If not, add the lime juice with 2 hours to go.
You will need a large frying pan, ideally cast iron. Start getting it hot. Take the meat out of the fridge and wipe it dry with paper towels. You want it pretty dry. Coat it in 1 tablespoon of the canola oil. When the pan is hot, I mean hot as in starting to smoke, about 500 to 600F, lay the flank steak in the pan. If you happen to have a bacon press, put it on the meat, If not, no big deal. Let it sit there for 3 minutes. Turn the meat and let it cook another 2 to 4 minutes, depending on how you like your meat. I only give it the 2 minutes because the flank steak will cook a bit more via carryover heat when it's on the cutting board. Move it to the board.
Coat the vegetables in the remaining canola oil and add them to the hot pan. Stir fry a minute, then let them sit a bit to get some char. Move them once a minute for 3 minutes. You want them soft, but not mushy, and with some browned or even blackened bits. Turn off the heat and mix in the lime juice and cilantro, as well as salt and lots of black pepper.
Slice the flank steak against the grain, and serve with the vegetables in tortillas and topped with avocado.
NOTE: I make my tortillas before I even start making the fajitas, keeping them in a plastic tortilla warmer. If you are reheating premade tortillas, you can do that either before you start or while the meat is searing.