Preheat your oven to 400°.
Stab each potato 2-3 times and microwave for 7-10 minutes, or until they are soft.
Meanwhile, in a medium skillet over high heat, saute the onion for 3-4 minutes, or until translucent. Add the BBQ sauce and chicken and stir until well combined. Set aside.
Cut the potatoes in half lengthwise and using an oven mit, carefully scoop out the flesh of the potato, being sure to leave a 1/4" in tact around the entire skin. This helps the potato hold its shape.
Add the potato flesh to a mixing bowl and add 2/3 c. cheese, Greek yogurt, milk, salt, onion powder and chili powder. Beat until smooth and creamy. Spoon the potato mixture back into the potato skins and using the back of the spoon, create a divot in the center of each potato.
Add a spoonful of the BBQ chicken and onion mixture into the center of each potato. Top with the remaining 1/3 c. shredded cheese and bake at 400° for 15 minutes.
Serve immediately topped with cilantro.