Preheat oven to 350°F. Spray an 8-inch round deep cake pan with baking spray with flour.

For browned butter: In a medium saucepan, melt butter over medium heat. Cook until butter turns a medium-brown color and has a nutty aroma, about 10 minutes. Remove from heat, and let cool to room temperature.

For streusel: In a medium bowl, whisk together flour, brown sugar, cinnamon, and salt. Stir in butter until mixture is crumbly. Crumble with your fingertips until desired consistency is reached. Stir in pecans.

For cake: In the bowl of a stand mixer fitted with the paddle attachment, beat eggs, banana, pineapple, and vanilla at medium speed until combined, 1 to 2 minutes. Stir in browned butter.

In a medium bowl, whisk together flour, ¾ cup (150 grams) granulated sugar, brown sugar, salt, baking powder, and ½ teaspoon (1 gram) cinnamon. Gradually add flour mixture to browned butter mixture, beating just until combined.

In a small bowl, stir together remaining 1 tablespoon (12 grams) granulated sugar and remaining ½ teaspoon (1 gram) cinnamon. Spread half of batter into prepared pan. Sprinkle with one-third of streusel and cinnamon-sugar mixture. Top with remaining batter, smoothing top with an offset spatula. Sprinkle with remaining streusel.

Bake until a wooden pick inserted in center comes out clean, 45 to 50 minutes, loosely covering with foil to prevent excess browning, if necessary. Let cool in pan for 15 minutes. Run a sharp knife around edges of cake to loosen sides. Invert onto a plate, and then invert again onto a wire rack.

For glaze: In a small bowl, whisk together confectioners’ sugar, sour cream, and milk. Pour over warm cake.