Hummingbird Sheet Cake

Preheat oven to 350°F. Coat a 13- x 9-inch baking pan with baking spray; line bottom of pan with parchment paper. Whisk together flour, baking powder, cinnamon, salt, and baking soda in a medium bowl.

Beat granulated sugar and butter in a stand mixer fitted with a paddle attachment on medium-high speed until mixture is pale and fluffy, about 3 minutes. Add eggs, 1 at a time, beating just until blended after each addition, about 1 minute. Reduce mixer speed to medium; beat in vanilla and mashed bananas until combined, about 30 seconds. Gradually add flour mixture in thirds, beating on low speed just until combined after each addition, stopping to scrape down sides as needed. Use a spatula to fold in pineapple and pecans.

Spoon batter into prepared pan, spreading evenly. Bake in preheated oven until golden around edges and a wooden pick inserted in center of cake comes out clean, 30 to 35 minutes. Transfer pan to a wire rack, and cool completely, about 1 hour, 30 minutes.

Beat butter in a stand mixer fitted with a paddle attachment on medium-high speed until smooth and creamy, about 2 minutes. Add cream cheese; beat until light and fluffy, about 3 minutes. Add vanilla; beat until well blended, about 30 seconds. Reduce speed to low; beat in 1 cup of the powdered sugar until well blended, about 30 seconds. Add kosher salt and remaining 1 cup plus 2 tablespoons powdered sugar, and beat until smooth and combined, about 1 minute. Chill until ready to use.

Spread frosting over cake. Form flowers on top of cake with dried pineapple rings. Fill center of each flower with white pearl sprinkles; garnish with mint leaves.