Preheat oven to 350ºF.
Peel and dice mango (save the pit to snack on later!).
Combine cinnamon and 1/2 cup sugar in a large mixing bowl. Reserve 1 TB of the mixture and set aside.
Cut the biscuits into quarters & toss with cinnamon sugar mixture to coat. Stir in the mango.
Divid coated biscuit mixture among a 12-cup greased or lined muffin tin (recommend silicone liners).
Stir the remaining 1/2 cup sugar into the melted butter. Pour the melted butter-sugar mixture over the cake mixture in the muffin cups. Sprinkle the remaining cinnamon-sugar mix on top. Bake for 20-25 minutes.
Remove from oven and sprinkle chopped pistachios on top. Let cool and enjoy!
Store leftovers in fridge and reheat leftovers in a 350ºF convection oven for 8-10 minutes.