Heat 1 tablespoon butter in a skillet over medium heat. Add coconut flakes. Cook and stir until lightly brown, 2 to 3 minutes; set aside to cool.

Place 1/4 cup butter in a microwave-safe bowl. Heat in the microwave until melted, about 1 minute. Allow to cool slightly. Crush cookies into the butter; stir to combine. Press crust into the bottom of a 4-inch springform pan.

Pour butterscotch topping onto the crust; spread to coat. Put crust in the freezer until hardened, about 10 minutes. Remove ice cream from freezer to soften at the same time.

Spread softened ice cream gently over the crust, using a warm spoon to make it even. Return cake to the freezer to harden, about 10 minutes more. Spread the toasted coconut over the cake.