Heat oven to 350 degrees. Line the bottom of a 9 x 9 pan with foil. Lightly spray with cooking spray.Add the oats, almonds and pecans to a baking sheet and bake until golden brown and toasted, 3-5 minutes. Transfer to a large bowl and set aside. Turn oven off.
Meanwhile add butter, honey, brown sugar, vanilla and salt to a small saucepan. Stir until just melted and the sugar dissolves.
Pour the butter into the oat and nut mixture, mix well. Allow the mixture to cool for 5-10 minutes before folding in the chocolate chips.
Transfer the mixture to the prepared pan and firmly press the mixture down with a spatula. This is important to making it stay together.Place in the refrigerator for 2 hours to firm up.
Lift up the bars out of the pan by grabbing the sides of foil.Cut into 12 bars and store in an airtight container in the refrigerator for up to a week.