In a medium bowl, whisk together the all-purpose flour, instant vanilla pudding mix, baking soda, and salt. Set aside.

In the bowl of a stand mixer fitted with the paddle attachment (or in a large bowl with a hand mixer), cream together the softened unsalted butter, granulated sugar, and light brown sugar on medium speed until light and fluffy, about 2-3 minutes.

Beat in the large egg until well combined. Then, add the mashed ripe banana and vanilla extract, mixing until just incorporated. Scrape down the sides of the bowl as needed.

With the mixer on low speed, gradually add the dry ingredient mixture to the wet ingredients, mixing until just combined. Be careful not to overmix.

Gently fold in the white chocolate chips and the coarsely crushed vanilla wafers using a spatula.

Cover the bowl with plastic wrap and chill the cookie dough in the refrigerator for at least 30-60 minutes. This step is crucial to prevent the cookies from spreading too much.

Preheat your oven to 350°F (175°C). Line two large baking sheets with parchment paper.

Using a medium cookie scoop (about 1.5 tablespoons), drop rounded balls of dough onto the prepared baking sheets, spacing them about 2 inches apart.

Bake for 11-13 minutes, or until the edges are lightly golden brown and the centers are set. The cookies might look slightly underbaked in the middle, but they will continue to bake on the hot pan.

Let the cookies cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.