Butterfly the flank steak if it is not already cut thin. Season all sides of the steak with sea salt and pepper, then spread chimichurri marinade over all sides. Cover securely and let it marinate over night in the fridge. Simple Mexican steak marinade: chimichurri or authentic carne asada marinade.
Make the homemade habanero salsa if using homemade hot sauce.
Follow the instructions for perfect instant pot rice here and pinto beans instant pot recipe here. The onion, garlic, bay leaves and oregano are used here.
Heat a cast iron or other heavy bottomed pan on medium heat and add a tablespoon of olive oil. When the pan is hot, sear the flank steak on both sides until a dark brown crust forms in spots. Approximate sear time on each side 5 minutes. Remove and allow to rest for 10 minutes. When cooled, slice against the grain and then cut into small bite-sized cubes.
Wash the lettuce and tomatoes. Prep the produce by shredding the lettuce and dicing the tomatoes.
Heat the tortillas one at a time in a large skillet or directly on a flat top griddle. Make sure that the tortillas don’t get crispy, we are looking to warm them so they can stretch and flex easily to mitigate ripping.
Assemble the burritos: Place the warm tortilla down and spread out a scoop of rice first and then pinto beans. Spread out the steak next, then cheese, salsa or hot sauce, tomatoes and lettuce on top.
How to roll a burrito: orient the shell so that the contents are in a short line horizontally. Take both hands and grab each side (right and left side of contents) and fold sides towards the center. Next, take the open side closest to you and fold it over the contents(away from you, towards the other side) and pull it back towards you to shape up the burrito shape, tuck it in tight and then roll the burrito up(away from you).
Wrap foil or parchment paper around the bottom half to help hold the burrito hold together while eating.