Step 10:

And add about 1tbsp of fish sauce:

I've got to admit, I don't follow measurements when adding those three things. I've been cooking this dish long enough that the process is pretty much 100% instinctive. Besides - if you want to adjust the flavour of the food, you can test the food and add more ingredients as required.
   
 
Step 11:

So anyway, now that you've added all that stuff, it's time to add all that basil. Add loads - it reduces in size significantly.