Trim and prep the skirt steak. Leave whole or cut into flat pieces for even cooking.

In a bowl or zip-top bag, mix together all marinade ingredients.

Add the beef and coat it well. Seal and marinate in the fridge for 2 to 6 hours (4 hours is ideal).

While the grill is heating, slice the onion, poblano, and bell pepper into uniform strips and place them in a disposable aluminum pan.

After the meat has marinated, lay it on top of the sliced vegetables in the pan. Pour in about 1/2 cup of the leftover marinade.

Grill the meat directly over high heat until it reaches an internal temperature of about 135°F.

Move the meat to the side of the grill. Place the pan with vegetables directly over the coals and let it simmer for about 3 minutes.

Return the meat to the pan with the veggies. Remove from heat and let everything rest and cool for 5 to 10 minutes.

Slice the meat thin against the grain and serve in warm tortillas.