Marinade skirt steak with garlic, oregano, cumin, salt and pepper, red pepper flakes, chopped cilantro, soy sauce, and lime juice. Set them aside for at least 1 hour or leave them overnight in the refrigerator.
Prep the ingredients per the instructions above.
Mix together the water and lemon. Refrigerate until ready to serve.
Make the sauce: Whisk all the ingredients together in a bowl. Season with salt and pepper. Set aside.
Make the pico: mix all the ingredients in a bowl. Season with salt and pepper to taste. Set aside.
Make the guacamole: Mash the avocado in a bowl with a fork; and add the cilantro and onion. Add a squirt of lemon to taste. Season with salt and pepper to taste. Refrigerate until ready to use.
Heat a grill pan on medium heat. Cook the steak for about 2 minutes on each side.
Rest the steak for 5 minutes. Then slice into bite-sized pieces.
Place a tortilla on a nonstick skillet over medium heat. Add Mexican cheese blend, chopped steak, and then more cheese on top. Fold in half. Cook until golden brown, then flip to the other side and cook until the cheese is melted and that side is golden brown.
Open up your quesadilla. Add the Pico and drizzle the sauce inside (or serve on the side if desired).
Cut into wedges; serve with guacamole and chips and lemon water.