Preheat the oven to 425°F (220°C).

Place the flour, brown sugar, baking powder, baking soda, salt, and cinnamon in a large mixing bowl. Whisk until the ingredients are evenly distributed.

Add the chilled butter cubes. Using a pastry cutter, fork, or your fingertips, work the butter into the flour mixture until the texture resembles coarse crumbs. This process generally takes about 2–3 minutes when done by hand.

Create a well in the center of the flour-and-butter mixture. Pour in the buttermilk and vanilla, then add the mashed bananas and thoroughly drained crushed pineapple.

Stir with a large spoon just until the mixture begins forming a dough. The consistency may remain somewhat sticky.

Gently fold in the shredded coconut. If necessary, use your hands to finish bringing the dough together. Lightly flour both your hands and the work surface to prevent excessive sticking.

Divide the prepared dough into two equal portions. On a lightly floured surface, gently pat each portion into a circle measuring approximately 6 inches across.

Slice each round into either 6 or 8 wedge-shaped pieces.

Arrange the wedges on a baking sheet with space between each scone. Bake in the preheated oven for 10–12 minutes, or until the scones develop a light golden color.

Remove them from the oven and allow them to cool before applying the glaze.

While the scones bake, add the chopped pecans and unsweetened coconut flakes to a nonstick skillet set over medium-low heat.

Toast for several minutes, stirring or tossing the mixture frequently, until the coconut becomes golden brown. Watch carefully because coconut can darken and burn rapidly.

Remove the skillet from the heat and reserve the toasted mixture for garnishing.

Place the room-temperature mascarpone in a large bowl and whisk until smooth and creamy.

Gradually blend in the confectioners' sugar, followed by the vanilla extract.

Slowly pour in 4 tablespoons of milk while whisking continuously. Continue mixing until the glaze is completely smooth and free from lumps.

If a thinner consistency is required, incorporate additional milk 1 tablespoon at a time, whisking thoroughly after each addition.

Once the baked scones have cooled slightly, spoon, drizzle, or spread a generous layer of mascarpone glaze across their tops.

Immediately scatter the toasted pecans and coconut flakes over the glaze.

Serve the finished hummingbird cake scones promptly.