¾ cup (170 grams) unsalted butter, softened and divided
½ cup (110 grams) plus ⅓ cup (73 grams) firmly packed light brown sugar, divided
2 tablespoons (30 grams) cream of coconut
½ tablespoon (7.5 grams) water
2½ teaspoons (10 grams) vanilla extract, divided
3 bananas (372 grams), halved lengthwise
½ cup (100 grams) granulated sugar
2 large eggs (100 grams)
1¾ cups (219 grams) all-purpose flour
1½ teaspoons (7.5 grams) baking powder
¾ teaspoon (2.25 grams) kosher salt
¼ teaspoon ground cinnamon
¾ cup (180 grams) whole milk
½ cup (25 grams) sweetened flaked coconut
¼ cup (60 grams) sour cream
Instructions
Preheat oven to 350° (180°C). Spray a 9-inch square cake pan with cooking spray.
Sprinkle walnuts around edges of prepared pan.
In a large saucepan, melt ¼ cup (57 grams) butter over medium-high heat. Stir in ⅓ cup (73 grams) brown sugar and cream of coconut; bring to a boil. Stir in ½ tablespoon (7.5 grams) water and 1 teaspoon (4 grams) vanilla; cook for 1 minute. Pour mixture into pan. Arranged halved bananas on syrup in bottom of pan, cut side down.
In a large bowl, beat granulated sugar, remaining ½ cup (110 grams) brown sugar, and remaining ½ cup (113 grams) butter with a mixer at medium speed until fluffy, 3 to 4 minutes, stopping to scrape sides of bowl. Add eggs, one at a time, beating well after each addition. Stir in remaining ½ teaspoons (6 grams) vanilla.
In a medium bowl, whisk together flour, baking powder, salt, and cinnamon. Reduce mixer speed to low. Gradually add flour mixture to butter mixture alternately with milk, beginning and ending with flour mixture, beating just until combined after each addition. Fold in coconut and sour cream. Carefully spread batter onto bananas.
Bake until a wooden pick inserted in center comes out clean, 50 to 55 minutes. Let cool in pan for 10 minutes. Invert onto a wire rack, and let cool completely. Store in an airtight container in refrigerator for up to 3 days.
Recipe by Bake from Scratch at https://bakefromscratch.com/banana-upside-cake-walnuts-coconut/