Preheat oven to 325 degrees. Line two baking sheets with parchment paper. Set aside.
In the bowl of a standing mixer, mix the butter and sugars on medium speed until combined.
Add the egg and mix until combined.
Reduce mixer speed to low. Add the flour, vanilla paste, baking soda and salt. Mix to combine.
Add the oats and chopped chocolate and mix until just incorporated.
Using an ice cream scoop, place dough balls equal distance apart on the prepared baking sheets. Bake for 12 minutes.
Remove from oven and bang the baking sheet on the counter top several times to collapse the cookies. Return to oven and bake for 3 minutes until slightly golden.
Cool on wire racks or enjoy warm!