Begin by preheating your oven to 350°F (175°C). Line your baking sheets with parchment paper to prepare for the cookies.
In a large mixing bowl, use an electric mixer to cream together the softened unsalted butter, brown sugar, and white sugar until the mixture is light and fluffy. This should take about 2-3 minutes.
Add in the two large eggs and one egg yolk, along with the vanilla extract. Mix until the ingredients are well combined and smooth.
Sprinkle the banana instant pudding mix into the mixture and blend until fully incorporated. The pudding will bring a lovely banana flavor and enhance the cookie's softness.
In a separate bowl, whisk together the flour, baking soda, and salt. Gradually add the dry ingredients to the wet mixture, mixing just until combined. Be careful not to overmix.
Gently fold in the white chocolate chips, ensuring they are evenly distributed throughout the dough.
Using a cookie scoop, drop rounded tablespoons of dough onto the prepared baking sheets, leaving space between each cookie. Bake in the preheated oven for 10-12 minutes, or until the edges are lightly golden.
As soon as the cookies come out of the oven, sprinkle a few extra white chocolate chips on top for decoration. Allow the cookies to cool on the baking sheets for a few minutes before transferring them to a cooling rack to cool completely.
