Slice chicken breast into thin pieces and add spices,tossing to coat, refrigerate for about 30 minutes.Shred cheeses.
Peel onion and slice in half,then slice the onion thin,place in skillet on med heat with 2T olive oil and caramelize,usually takes about 10-15 minutes.
In a seperate skillet (I like to use my cast iron) add 2T olive oil,put on medium high heat till skillet gets hot,add chicken breasts and sear on both sides till done,you want the chicken to be blackened but not burnt,this should take about 5 minutes,just make sure the skillet is hot.
To prepare the quesadillas butter one side of flour tortilla and place in skillet or griddle on medium high heat,butter side down.
Add 1/3- 2/3c mexican blend cheese to tortilla, (sprinkling around the whole tortilla),then add the smoked cheddar,about 1/4c (do not overdo the smoked cheddar because it will be to strong).
Add the chicken pieces (just handful or however much you like) to one side of the tortilla,like you are making an omelet,then follow suit with the onions,as much as you like.
Fold tortilla over as in an omelet and"fry" till lightly brown and crispy,then flip over and do the other side.
Slice into wedges and serve with sour cream,salsa,guacamole.
This recipe will make 3-4 large tortillas,depending on how much ingredients you use per tortilla,the amount I have posted is only a guideline,use as little or as much as your liking.