Position racks in the upper and lower thirds of the oven and preheat oven to 180 C/160C Fan/350F
Line 2 baking sheets with parchment paper or silicone baking mats.
240 grams old-fashioned rolled oats, 1 teaspoon baking soda, 3/4 teaspoon salt, 200 grams all-purpose flour
In a large bowl, whisk oats, flour, baking soda, and salt to blend well.
165 grams unsalted butter, 1 tbsp pure vanilla extract, 140 grams dark brown sugar, 90 grams granulated sugar
In the bowl of a stand mixer fitted with the paddle attachment, beat butter and vanilla extract on medium high speed until blended and creamy. Add sugars and beat until light and fluffy, about 2 minutes.
2 large eggs, 200 grams white chocolate
Beat in the eggs 1 at a time. Reduce mixer speed to low and gradually add oat mixture, then add the chopped white chocolate.
Scoop the batter, 2 tbsp at a time, onto prepared baking sheets, about 8 cookies to a sheet.
2 tbsp sea salt flakes
Sprinkle a few sea salt flakes onto each cookie.
Bake for 12 – 14 minutes until the cookies are golden around the edges but still a bit soft in a centre.
Rotate the baking sheets from front to back and top to bottom half way through baking. Do not over bake.
Let cookies cool on the baking sheets for 2 minutes and then transfer them to a wire rack to cool completely.