Grease an 8x8-inch baking dish with cooking spray. Set aside.
In a large pan of boiling water, cook the sweet potato cubes for about 10 minutes.
Drain the sweet potato cubes and transfer into a bowl.
With a potato masher, mash sweet potato cubes.
In the bowl of mashed sweet potato, add the coconut milk, ¼ cup of brown sugar and cinnamon and with a fork, mix until well combined.
Place the mixture into the prepared baking dish evenly.
For topping: in a large bowl, add the remaining brown sugar, pecans, flour and cinnamon and mix well.
Add the melted butter and mix until a crumbly mixture forms.
Sprinkle the topping mixture on top of sweet potato mixture evenly.
Slide the Air Fryer Basket inside and adjust the temperature to 340 °F to preheat for 5 minutes.
After preheating, arrange the baking dish into the Air Fryer Basket.
Slide the basket into Air Fryer and set the time for 16 minutes.
After cooking time is finished, remove the baking dish from Air Fryer and serve.