1¾ cups (219 grams) all-purpose flour3 tablespoons (36 grams) granulated sugar½ teaspoon (2.5 grams) baking powder1 teaspoon (2 grams) ground cinnamon¾ teaspoon (2.25 grams) salt¼ teaspoon (1.25 grams) baking soda6 tablespoons (84 grams) cold unsalted butter, cubed¼ cup (60 grams) cold whole buttermilk1 teaspoon (4 grams) vanilla extract½ cup (114 grams) mashed ripe banana (about 1 medium banana)¼ cup (67 grams) pressed drained crushed pineapple½ cup (57 grams) chopped pecans, toastedVanilla Cream Cheese Glaze (recipe follows)Garnish: chopped toasted pecans
Preheat oven to 375°F (190°C). Line a baking sheet with parchment paper.
In a large bowl, whisk together flour, sugar, baking powder, cinnamon, salt, and baking soda. Using your hands or a pastry cutter, cut in cold butter until it resembles course crumbs. Make a well in center.
In a medium bowl, whisk together cold buttermilk and vanilla. Add banana and pineapple. Add buttermilk mixture and chopped pecans to flour mixture, and stir with a spatula until dry ingredients are fully moistened. Knead with your hands once or twice just until dough is smooth and fully hydrated.
Turn out dough, and pat into a 6-inch circle. Cut into 4 equal pieces. Place on prepared pan.
Bake until golden and an instant-read thermometer inserted in center registers 205°F (96°C), 25 to 30 minutes. Let cool on pan for 10 minutes. Remove from pan, and let cool completely on a wire rack. Spread Vanilla Cream Cheese Glaze on top, and garnish with toasted pecans, if desired. Store in an airtight container for up to 3 days.