Preheat oven to 350°F. Beat butter, brown sugar, and vanilla at medium speed with an electric mixer 3 to 5 minutes or until creamy. Add eggs, 1 at a time, beating until blended after each addition.
Combine flour, cinnamon, baking soda, and salt in a medium bowl; gradually add flour mixture and mashed banana to butter mixture, beating just until blended. Add oats and next 2 ingredients; stir until blended.
Drop dough by heaping tablespoonfuls 2 inches apart onto 2 parchment paper-lined baking sheets. Flatten dough slightly with bottom of a glass dipped in flour.
Bake, in batches, at 350°F for 12 minutes or until golden. Cool on baking sheets 10 minutes. Transfer to wire racks, and cool completely (about 20 minutes).
For the frosting: Beat 2 cups sifted powdered sugar, 4 oz. softened cream cheese, 1 tsp. vanilla extract, and 1⁄2 tsp. kosher salt with an electric mixer 3 to 5 minutes or until creamy. Add 1⁄4 cup heavy cream, and beat until smooth.
Spread Cream Cheese Frosting over each cooled cookie (about 11⁄2 tsp. per cookie); sprinkle with banana chips, coconut, and toasted chopped pecans, pressing to adhere.
Recipe by Bakepedia at https://www.bakepedia.com/hummingbird-oatmeal-cookies/