Preheat your oven to 350°F (175°C). In a mixing bowl, combine gluten-free oats, melted coconut oil, and coconut sugar until fully incorporated. Press this mixture firmly into a pie dish. Bake for 10–12 minutes or until golden brown, then set aside to cool completely.

In a blender, combine ripe bananas, coconut milk, and tapioca flour. Blend until smooth and creamy, then pour this mixture into a saucepan and cook over medium heat, stirring continuously for about 5–7 minutes, or until thickened and bubbling. Remove from heat and allow to cool slightly.

Once cooled to room temperature, pour filling evenly into the cooled oat crust. Cover the pie with plastic wrap and refrigerate to set for at least 2 hours, or ideally overnight.

After chilling, remove the pie from the refrigerator. Top with sliced bananas and nuts. Slice into wedges and serve chilled.