Prep: Line a baking sheet with parchment paper and set aside.
Dry mixture: In a large mixing bowl, whisk together flour, sugar, baking powder, salt, and chocolate chips.
Cut the butter into the flour: Add the cold cubes of butter and toss to coat in the flour mixture. Break the butter down into small pea-sized pieces with a dough blender or by pressing them between your fingers. Make a well in the middle of the mixture and set aside.
Wet mixture: In a medium bowl, mash the bananas with the back of a fork. Add heavy cream and vanilla extract and whisk until combined.
Form dough: Pour the wet mixture into the well you created in the flour mixture and mix with your hand until it becomes a shaggy dough.
Press and shape dough: On a floured surface, turn out the dough. Coat your hands with flour and press the dough together into a flattened disc shape that's about 1-1.5" thick. Don't knead or overwork the dough.
Cut wedges: Use a bench scraper or a knife to cut the dough into 8 wedges. Transfer the wedges to your lined baking sheet, leaving about 1-2" in between each scone for spreading. Press a few extra chocolate chips on top of each scone (optional).
Chill and preheat: Chill the entire baking sheet in the fridge while you preheat the oven to 400°F.
Brush scones: Right before baking, use a pastry brush to brush a thin layer of heavy cream on top of each scone. Sprinkle coarse sugar on top of each scone for extra crunch.
Bake: Bake scones for about 20-25 minutes or until the edges are crisp and golden brown. Let the scones cool on the baking sheet for at least 10-15 minutes before transferring them to a wire rack to cool completely or enjoy them warm!