Preheat the oven to 350 degrees. Line cookie sheets with parchment paper or silicone mats.
Using a food processor, grind up the oats until they are a fine powder. Add the corn starch, baking soda, and sea salt to a food processor and combine. Set aside.
In a large bowl, using an electric mixer, beat the unsalted butter, white sugar, and brown sugar on high for about 1 minute.
Add egg and vanilla extract. Beat on medium for approximately 30 seconds until mixed well.
Add half of the oat mixture and fold in using a spatula. Once the first half is mixed in, add the second half and continue to fold in the oats until fully combined.
Stir in the chocolate chips until evenly dispersed throughout the dough.
Drop 2 tablespoon-sized dough balls (about 35g) onto the lined cookie sheet.
Baking time will be 9-11 minutes.
Remove from oven and let sit on cookie tray for at least 10 minutes to let the cookie set and become more stable.
Cool cookies completely on a wire rack.