Make the cookie dough: Place the cold cubed butter, brown sugar and regular sugar in a stand mixer. Use the paddle attachment and cream for 5 minutes on medium.
Prep the dry ingredients: While the sugars and butter are creaming, in a separate bowl mix together the flour, cornstarch, baking soda and salt. Don't add the flour mixture yet, just leave until needed.
Add the eggs: Stop the mixer and scrape down the sides and add the eggs and mix well for a minute. Scrape down the sides again.
Now add the flour: Stop the mixer and add in the flour mixture. Stir on slow just until the flour is blended in.
Add the fillings: Stop the mixer and scrape down the sides and add in the Saba cubes, banana chips, langka chips, and toffee bits. Mix on low just until everything is coated in Turon Cookie dough.
Turon on oven: Leave the dough to rest while you pre-heat the oven to 410F and line your baking sheets with parchment or silicon baking mat.
Bake the Turon Cookie Dough: Using a ½ cup measuring cup, scoop the Turon Cookie dough balls on the prepared baking sheet. Only put 4 scoops on at a time as they are big cookies and spread a bit. Bake in the oven for 9-10 minutes. Just until the outside of the cookie is nice and golden and looks crisp. Cool the cookies: Take out of the oven and leave to cool on the baking sheet for 5 minutes. After 5 minutes transfer the cookies to a wire rack to fully cool down.
Repeat baking steps until all the dough is cooked. You should be able to make 16 cookies with this recipe.