Melt the butter over medium heat and leave it to cool a little bit.
In a medium bowl whisk together flour, sugar, baking soda and salt. Then add the chocolate chips and rolled oats and whisk until everything is well combined.
Beat the egg with a small whisk or fork and mix with butter and vanilla extract.
Add the wet ingredients to dry ones and combine them using a wooden spoon or your hands for a better result.
Using your hands form balls of cookie dough and place them on a cookie sheet lined with baking paper leaving 2 inches between each ball.
Bake for 10-12 minutes. They will be soft in the middle when done but will harden a little once they cool.
Transfer to a cooling rack to cool completely. Pour yourself a glass of milk and enjoy! :)
Notes
*I didn't have chocolate chips so I chopped a chocolate bar. If you want that uneven rustic look you can use chopped chocolate as well. **You don't want to overbake these cookies. It's better if they are slightly underbaked.