You will bake the cookies until almost done. They will set up and continue baking with the residual internal heat after they're pulled out of the oven.
They will be VERY soft just out of the oven so let them rest for a while; when cooled they will be firm enough to handle and quite delicious.
If your peanut butter is not on the salty side add 1/4-1/2 tsp salt to the batter.