Oats Water Sugar Brown Sugar Butter
In a separate large bowl, add the white sugar and 1 cup brown sugar, as well as 1/2 cup of the softened butter. Beat that together with an electric hand or stand mixer until it becomes well combined and fluffy.
Add the vanilla extract and eggs and continue to beat that together until smooth. Once smooth, add the dry ingredients to the wet ingredients, as well as the soaked oats. Add the batter to the greased baking dish, and spread it out evenly with a spatula.