Preheat oven to 350°F and line an 8x8 pan with parchment paper. In a large bowl, mix together the base/crumble ingredients. Press ⅔ of the dough into the prepared pan.
Bake the base for 10 min. In a small saucepan, cook the mango until it is soft and mushy. Mix in the maple syrup and vanilla extract. Stir in the tapioca flour and continue cooking until the mixture begins to thicken.
Spread the mango filling over the baked base and crumble the remaining ⅓ of the dough evenly over top. Return to the oven to bake for 16-18 min. or until the crumble on top begins to turn golden. Let cool completely before slicing and enjoying!
