Step 1

For the marinade: In a small 2 cup measuring cup, or something similar size and shape, combine all the marinade ingredients. Using an immersion blender, puree the marinade until smooth. Transfer to a re-sealable plastic bag and add the steak, seal and shake to coat. Refrigerate the beef for 2 to 4 hours to tenderize and flavor the beef.

Step 2

Preheat a ridged grill pan on high heat.

Step 3

Drain the marinade from the beef. Lightly oil the grill or grill pan. Season liberally with salt and freshly ground black pepper. Grill the steak over medium-high heat and cook for 4 minutes on each side and then transfer to a cutting board and let rest. Depending on the size of your grill pan you may need to cook in batches.

Step 4

For the fajitas: Once the beef is off the grill pan and resting, add the bell peppers and onions tossed with lime juice and olive oil, if using. Grill the mixture for 7 to 8 minutes until the vegetables are just barely limp.

Step 5

While the peppers and onions are cooking, heat up the tortillas. Turn any free burners on a medium low flame. Place a tortilla on each flame and let it char about 30 seconds to 1 minute, flip the tortilla and repeat on the second side. Once heated and charred remove the tortilla to a clean tea towel and wrap to keep warm. Repeat until you have warmed all of your tortillas.

Step 6

You can also heat your tortillas in a microwave, lightly dampen a tea towel with some water, wrap the tortillas in the damp towel and heat in the microwave for about 1 minute. Check to see if they are warm, if not repeat the heating at 1 minute intervals until they are warm and pliable.

Step 7

Thinly slice the steak against the grain on a diagonal.

Step 8

To serve: Spread some guacamole on a tortilla, top with a few slices of steak, peppers and onions, and salsa. Roll up the tortilla to enclose the filling.

Step 9

May also be served with sour cream and shredded cheese.

Step 10

Halve and pit the avocados. With a tablespoon, scoop out the flesh into a mixing bowl. Mash the avocados with a fork, leaving them still a bit chunky. Add all of the rest of the ingredients, and fold everything together.

Step 11

Lay a piece of plastic wrap directly on the surface of the guacamole so it doesn't brown and refrigerate for at least 1 hour before serving.