Preheat the oven to 350°F.
Melt butter in a small saucepan over low heat; set aside to cool.
In a large bowl, combine the oats, brown sugar, granulated sugar ,flour, and salt.
Add the melted butter, eggs, and vanilla; mix until blended thoroughly.
Line baking sheets with parchment paper or silicone mats.
Drop rounded tablespoons of batter about 2 inches away from each other.
Bake for about 8-10 minutes, or until the cookies have spread flat and are a deep golden-brown color.
Remove from the oven and cool completely on the pan.
Using an offset spatula, gently remove each cookie and place on a serving tray.
Keep doing this until no dough is left.
Let cool and harden completely.
Enjoy!!!