Using sauté setting – add oil and onions to pot. Let them begin cooking, not stirring too frequently because you want them to caramelize and get some color on them. After about 5 minutes, add the aromatics (ginger, cloves, star anise, coriander seeds, and black peppercorns). Continue cooking for 5 more minutes, so that the onions have cooked about a total of 10 minutes.
Add chicken thighs to pot (skins removed and set aside) along with chicken broth, fish sauce, salt, and sugar. Lock lid and cook for 15 minutes at high pressure.
Meanwhile – spread out chicken skins on a baking sheet, season with salt and pepper, and cook under high broiler for 10-12 minutes, or until desired crispiness and char is achieved. Set aside on paper towels until ready to serve. (This is an optional and also non-traditional step. But it’s delicious and adds some great texture to your bowl.)
You can also prepare all of your garnish toppings at this point.
Once cook time is complete, allow pressure to release naturally for at least 15 minutes. Then quick-release remaining pressure.
Transfer chicken thighs to a bowl and remove meat from bones in bite-size pieces.
Using a fine mesh strainer (or a colander lined with cheesecloth), pass broth though to strain then return to pot. Keep broth warm until ready to serve, but bring back up to a boil first. You can do this using the sauté setting.
Prepare rice noodles according to directions on package.
Place 1 serving of noodles in bowl. Then add chicken, sliced onions, and herbs to bowl. Finally, pour boiling broth over noodles and chicken. Serve immediately.