Preheat the oven to 350º F. Spray a 9×13-inch baking dish with cooking spray. Line with parchment paper if desired.
In a large mixing bowl, use an electric mixer to cream the butter and sugar together for 2-3 minutes. Add in the eggs and vanilla. Mix for another 2 minutes. 1 cup salted butter, 2 ⅓ cups light brown sugar, 2 large eggs, 1 teaspoon vanilla extract
Add the flour, salt, baking soda, baking powder and quick oats. Mix until combined. The batter will be very thick. Fold in the chocolate chips. 2 ½ cups all-purpose flour, 1 teaspoon salt, 1 teaspoon baking soda, 1 teaspoon baking powder, 1 ½ cups quick cook oats, 2 cups mini chocolate chips
Spread the cookie dough in the prepared pan. Press extra chocolate chips into the top of the bars. ¼ cup semi-sweet chocolate chips
Bake for 30 minutes or until the edges are golden brown and the bars look slightly puffed all over. The bars will be very gooey right when they come out of the oven. Allow them to cool slightly before you slice them.
