Set your oven to 400°F and grease a large casserole dish lightly.
Heat the olive oil in a large skillet and add the garlic and sliced red onion, cooking gently for about 1 minute.
Stir in the chopped kale and shredded chicken, cooking for an additional 3 minutes over medium heat until the kale has softened.
Pour in the coconut milk and add the fresh thyme, bringing the mixture to a boil.
Add the sliced sweet potatoes and sea salt, reducing the heat to low and simmering for 7 to 10 minutes.
Transfer the skillet contents carefully into the greased casserole dish.
Place the dish in the oven and bake for 15 to 20 minutes, or until the sweet potatoes are tender and have absorbed the coconut milk.