Whisk together flour, baking soda, and sea salt in a large bowl. Using the funnel or paper cone, pour flour mixture into the bottom of the glass jar. Spread evenly with spatula or spoon to form a flat layer.
Add layer of oats. Spread evenly to form a flat layer.
Next, add brown sugar. Again, spread evenly.
Add granulated sugar and spread evenly.
Lastly, add chocolate chips and seal jar tightly with lid and ring