Place Boneless, Skinless Chicken Thigh (2 pound) in a ziplock bag and pour half of the bottle of Spiedie Sauce (1/2 jar) over the thighs. Move the thighs around in the marinade for even coverage and refrigerate for at least one hour up to overnight.
Place Yellow Squash (2), Zucchini (2), Red Onion (1), and Assorted Color Bell Peppers (12) in a ziplock bag. Pour the remaining Spiedie Sauce (1/2 jar) over the vegetables and refrigerate for 1 hour as well.
Set up a charcoal grill for direct heat grilling adding a couple small chunks of your favorite wood on the hot coals for smoke flavor.
Remove the chicken thighs from the marinade and place on the grill. Season each thigh with Greek Seasoning (1 ounce) as they cook. Total cook time is about 10 minutes. Place each thigh on a platter and cover loosely with aluminum foil.
Remove the vegetables from the marinade and place on the grill. Season with remaining Greek Seasoning (1 ounce) and cook for 3-4 minutes on each side or until tender, turning as needed.
Warm the Pita Bread (to taste) for 30-45 seconds on the grill. Slice the thighs into bite size pieces and place on a platter along with the grilled vegetables. Serve family style with Lettuce (to taste), Tomato (to taste), Crumbled Feta Cheese (to taste) and Tzatziki (to taste).