Twice Baked Sweet Potatoes

4 to 6 sweet potatoes, baked, peeled, and mashed
1/4 to 1/2 cup plain yogurt
1/2 cup shredded cheddar cheese, divided
2 to 4 TBSP chopped chives or green onions
6 slices turkey bacon, cooked and chopped, divided

Mix sweet potatoes, yogurt, half of the cheese, green onions, and most of the bacon in a large bowl.  Pour into greased baking dish and smooth.  Sprinkle remaining cheese and bacon over the top.  Bake at 350 for approximately 30 minutes.