- Roughly chop the ginger, leaving the skin on. 
- Remove the skin from the onion and roughly chop. 
- With your Instant Pot set to sauté mode, high heat, add the spices (cinnamon, cloves, star anise, and fennel seeds), and toast them until fragrant. 3-5 minutes 
- Add the ginger and onion and continue to cook on sauté until they start to blacken. It’s ok if the spices begin to burn a little. 
- Turn the Instant Pot heat off and carefully pour in the water. It is going to spit and splash, so be extra careful. 
- Add the meat products to the water and the apple. Cover and set the cooker to high pressure for 1 hour. 
- When the hour is up, let the cooker rest pressurized for another 30 minutes.  
- Carefully release the pressure and remove the lid. 
- Strain away the solids from the stock using a colander. 
- Strain the stock once again using a fine mesh strainer or cheesecloth.  
- The meat will have given up most of its flavor at this point; however, I like to shred any beef or chicken I can and add those to my topping list for a little extra flavor and texture. Otherwise, you can use it for another purpose or discard it. 
- Stir in the fish stock and adjust salt and pepper as desired. 
- Your pho stock is now ready! You can use this immediately or refrigerate it for up to a week. It also freezes very well and can be stored frozen for up to 6 months.  
- If you are going ahead and eating the same day, boil water and prepare your noodles per package instructions.