Preheat oven to 375°F (190°C) .Line a large baking sheet with a silicon mat or parchment paper. Set aside.
In a medium bowl, mix together the flour, baking soda, powder, and salt. Set aside.
In a large bawl with a hand mixer, beat the coconut oil and sugars for 1-2 minutes, or until the sugar dissolves into the oil. Lower the speed to medium-low, and mix in the eggs, mashed bananas and vanilla and beat until mixed .
Gradually add in the flour mixture, beating until a little flour remains. Fold in the chocolate chips an nuts with a rubber spatula.
Divide the dough into 20 even pieces. Shape the dough roughly into a ball.
Place on the prepared baking sheet, spacing 2 inches apart. Refrigerate for at least 30 minutes but up to 10 hours before baking.
Bake for 15-20 minutes, until light golden brown.
Recipe by Neta Cooks at https://netacooks.com/monster-chocolate-chip-cookies/