BBQ Chicken Packed Pita

From the guy on the Next Food Network Star!

* 1 pound boneless skinless chicken thighs (or a combination of breasts and thighs)
* ½ to ¾ cup BBQ rub, recipe follows
* Oil, for grilling
* ⅔ cup BBQ sauce, recipe follows or store-bought
* 1 tablespoon olive oil
* 2 cloves garlic, smashed
* 1 (8-ounce) bag washed baby spinach leaves (or 1 cup frozen, drained and chopped)
* Salt
* 2 tablespoons butter, softened
* 4 whole-wheat flat breads (such as naan or Mediterranean style pita)
* 6 ounces shredded Cheddar/jack cheese blend

Prepare a hot grill outside or preheat a grill pan to high heat and preheat oven to 375 degrees F.
Toss raw chicken in a bowl with rub, a few pieces at a time until all chicken is well coated. Grill chicken on well oiled grill or grill pan for about 2 minutes on each side, until nice grill marks are formed. If chicken pieces are very thick, finish cooking for 5 to 10 minutes more in the preheated oven. Allow chicken to cool a few minutes and then pull apart into nice shreds. Toss chicken with BBQ sauce so that it is well coated but not overly wet. Keep warm in a warm saute pan until ready to use.
Heat olive oil in large saute pan over medium-high heat. Stir in garlic with wooden spoon. After 30 seconds add spinach and turn off heat. Toss spinach in hot oil, when wilted completely season with salt. Set aside.
Spread butter evenly over 1 side of each pita. In a large saute pan, grill each flatbread over medium-high heat, buttered side down (work in batches if necessary) top each flatbread with 1½ ounces of cheese, ¼ of the spinach, and ¼ of the chicken. Fold each flatbread over and continue grilling until golden brown on each side. Cut in half crosswise, transfer to platter and serve.