I have several ways of making tacos and fajitas. Depending on who I'm making it for. One ingredient that is always the same is Taco Bells little sauce packs. We always have a bunch left over and I use these at home. For some reason it's not a taco without.
For the little ones a simple chicken taco is leftover chicken (I often bake 2 chickens and freeze one for tacos), shredded cheese, lettuce and hot sauce. If they ask for sour cream or refried beans I'll add them, but I don't always have them on hand.
Dh likes the Ortega Fajita seasoning packs, which I get for free with coupons. He likes his with lots of red, green peppers & onions, fried in 1 pan with oil, and the chicken, or sometimes beef in the other with a little water and seasoning. Then they're usually mixed together. We add sour cream, refried beans, cheese, lettuce, salsa (usually homemade), and guacamole (I've been using the wholly guacamole which I got free a year ago and froze. The separate packs are awesome because only 4 of us like guacamole.)
Now my favourite is our homemade crunch wraps, not quite like Taco Bells because they don't have the taco in the middle, but because of the way they're fried they're pretty crunchy anyway.
I like these with beef better. I cook the beef and add all the extras, nothing really special, but they taste great. Cook with the folded side face down first.