Sift together flour, salt, and baking soda. Set aside.
In a large mixing bowl, beat together the brown sugar, sugar, and butter until fluffy.
Beat in eggs, one at a time, then the vanilla. Stop to scrape the bowl down as needed.
Add the flour mix in 2 or 3 batches, mixing until just combined. Mix in the oats.
Cover the dough and chill for at least 1 hour.
Preheat the oven to 375 F and line cookie sheets with parchment paper.
Roll the dough into walnut sized balls, then place 2 inches apart on the cookie sheets. Gently flatten with a fork or the back of a spoon.
Bake until golden and chewy, about 8 to 10 minutes. 10 to 12 minutes will give you a crispier cookie.
Let cool on baking sheet for 5 minutes before transferring to a wire rack to cool the rest of the way.