Preheat oven to 325°F (170°C).

For cream cheese batter: In the bowl of a stand mixer fitted with the paddle attachment, beat butter at medium speed until smooth and creamy, about 1 minute, stopping to scrape sides of bowl. Add cream cheese, and beat until smooth and well combined, about 30 seconds, stopping to scrape sides of bowl. Reduce mixer speed to low; add sugar, beating just until combined. Increase mixer speed to medium, and beat until fluffy, about 2 minutes, stopping to scrape sides of bowl. Add eggs, one at a time, beating until well combined after each addition. Beat in vanilla bean paste. (Mixture may look slightly curdled at this point, but batter will come together.)

In a medium bowl, whisk together flour, salt, and baking powder. With mixer on low speed, gradually add flour mixture to butter mixture, beating just until combined and stopping to scrape sides of bowl. Transfer batter to a large bowl.

For banana batter: Clean bowl of stand mixer and paddle attachment. Using the paddle attachment, beat butter at medium speed until smooth and creamy, 30 seconds to 1 minute, stopping to scrape sides of bowl. Add cream cheese, and beat until smooth and well combined, about 30 seconds, stopping to scrape sides of bowl. Reduce mixer speed to low; add sugars, beating just until combined. Increase mixer speed to medium, and beat until fluffy, about 2 minutes, stopping to scrape sides of bowl. Add egg, beating until well combined. Beat in vanilla bean paste. (Mixture may look slightly curdled at this point, but batter will come together.)

In a medium bowl, whisk together flour, cinnamon, salt, nutmeg, and baking powder. With mixer on low speed, gradually add flour mixture to butter mixture alternately with banana, beginning and ending with flour mixture, beating just until some flour streaks remain. Beat in pecans just until combined.

Generously spray a 12-cup Bundt pan with baking spray with flour. Spoon banana batter into prepared pan in an even layer; gently spoon cream cheese batter onto banana batter in an even layer. Firmly tap pan on a kitchen towel-lined counter several times to settle batters and release as many air bubbles as possible.

Bake for 50 minutes; rotate pan, and bake until a wooden pick inserted near center comes out clean, crack on surface of cake appears mostly dry, and an instant-read thermometer inserted near center registers 208°F (98°C), 15 to 20 minutes more. Let cool in pan for 15 minutes. Carefully invert cake onto a wire rack placed over a rimmed baking sheet, and let cool completely.

For topping: Brush cooled cake with melted butter.

In a small bowl, stir together sugar and cinnamon. Cover cake with cinnamon sugar, pressing gently to help adhere. Sprinkle grooves of cake with additional cinnamon sugar, if desired.