Just want to make some quick correction
It's really important to have a nice clear broth when you making Pho. So after you Par boil the beef bones for 3 minutes, dump the water and bones in the sink and wash it with warm water. Do that for about 3 times.
Spices are not optional. It's
required. Peppercorns and coariander aren't the right spices either. To make a good pho, you'll need to roast funnels & Cinnamon stick (Saigon brand) before adding it to the stock, as well as star anise if you like its strong flavor. I personally dislike it because it's too overpower and kill the overall flavor.
Minimal simmering is about 4 hours. And I would also recommend to use Oxtails (They're figgin awesome after 4 hours of simmering)
And grilled chicken is a NO-NO D:
Try beef chuck, rump, brisket or cross rib roast, you'll find them so much more satisfy...as well as raw eye of round, sirloin, London broil or tri-tip steak, thinly sliced.
And as far as veggie go, don't use the regular cilantro as it doesn't really fit well with Pho. Thorny cilantro (
http://www.caribbeanseeds.com/culantro.jpg) is what you really want. You can find it at most asian market. It's essentially is the most important veggie to go with Pho ( And basil, bean sprout as you mentioned)
I have tried a lot of hot sauce to go with Siracha but really nothing sit better with it than Siracha. You can also put an equal amount of Hoisin sauce & Siracha in a dipping sauce and use it to dip the meat. It's pure awesome.