Quarter the onion and slice pepper and pu on top of roast.
Pour green salsa on top.
Cook 6-8 hours or until pork falls apart.
About 30 minutes before it's done, start the rice. You will also need to shred the pork now too. This should be very easy because it should just fall apart using 2 forks.
After you get the rice started, prepare your items to top the salsa verde. Simply shred the cheese and slice the avocado.