Preheat oven to 350°. Spray muffin tins with non-stick cooking spray.
Add olive oil, onions, peppers, and carrots to a skillet over medium heat. Sauté for about 7-10 minutes or until soft. Stir in garlic and balsamic, cook for another 1-2 minutes. Transfer cooked veggies to a plate or bowl to cool slightly.
In a large mixing bowl combine ground turkey, bread crumbs, beaten egg, poultry seasoning, Worcestershire, ketchup, seasoned salt and pepper. Stir in cooked vegetables. Divide turkey mixture evenly into the muffin tins, packing down with a spoon. You should get about 18 muffins if you fill them almost to the top.
In a small bowl, whisk together the BBQ sauce topping ingredients. Spoon evenly over each muffin. Bake for 35-40 minutes, or until centers reach 165° internal temp. Garnish with fresh or dried parsley flakes if desired.
I use silicone muffin tins that seem to be slightly deeper than a regular muffin tin, so if you're using a standard size, you may be able to make more muffins, or just don't fill them all the way full. The smaller they are, the faster they will cook through.