In a large skillet cook the bacon to a desired crispness; remove from pan and drain on paper towel-lined plate. Break up bacon in pieces when cool enough to handle.
Add green onions to bacon fat and cook until tender, about 1 minute. Remove and set aside.
Add butter to the skillet.
Season chicken with salt and pepper and add to pan with bacon fat and butter; brown chicken on both sides, about 3 minutes per side. Remove from pan and set aside.
Arrange carrots, onions, mushrooms, potatoes and garlic in the slow cooker; season with salt, black pepper and stir around.
Add chicken and skillet drippings to slow cooker and layer the crumbled bacon and green onions on top.
Pour in chicken broth and wine. Add thyme sprigs and bay leaves.
Cover and cook on LOW for 5 1/2 hours.
This part is optional, but follow it if you want a thicker sauce. IF you DO NOT want to thicken the sauce, continue to cook the dish for 6 hours.Remove 3 tablespoons liquid from slow cooker into a mixing bowl; whisk in the cornstarch until smooth. Pour into the slow cooker and stir until well combined.
Cover and continue to cook for 30 minutes.
When time is up, remove chicken and transfer to a cutting board; cut it up in pieces or shred it.
Stir chicken back into the slow cooker and serve.