There are a few steps to this so it kinda seems like a lot - but you can skip whatever you like and make it your own. This is how we do it:
2 boneless/skinless chicken breasts
Cover liberally with rub and set aside for a half hour or so while you do other stuff.
1/2 tsp each: chile powder, garlic, paprika, salt
1/4 tsp each: coriander, cumin, pepper
When the grill is hot, roast the two poblanos until black & blistered all over. Put them into a paper bag, seal it up and wait 10 min. Then peel off the charred skin and slice the soft peppers into strips. Set aside.
1 can refried beans
Heat these up on top of the stove with about a TB of bacon grease. It's worth it. Really.
1/2 Cup Chopped tomatoes
Sour Cream (stir in some chili powder & lime juice if you want to "fancy it up")
Other terrific toppings:
Roasted corn (grill it then slice it off the cob)
Fill your tortillas & enjoy.