Julienne the vegetables and combine them in a bowl.
Add crushed garlic and mix lightly.
Removed mushrooms stalks and slice the caps - add to the bowl. mix the oil and chili powder, cumin and oregano in a cup, pour over veggies, and stir well.
Set aside to marinate. Note: Carnivores should feel free to add sliced chicken/steak.
Make the guacamole (I'm sure you know how), cover tightly and chill out in a fridge.
Heat a frying pan or wok until very hot. Add veggies and stir fry over high heat 5-6 minutes, until the mushrooms and peppers are just tender (I prefer mine slightly charred). Of course, meat eaters will probably need to cook longer so as not to have a bio-hazard for dinner. Season with salt and pepper.
Spoon the filling on to the tortilla and roll up.
Garnish with cilantro and serve with guacamole and lime wedges.