For the minced pork, if it is good and fatty, use 450 grams (1 lb) of that. If the pork does not look really fatty, go with 350 grams (12 oz) of that and 100 grams (3.5 oz) of ground pork belly. Grinding the meats yourself is always best as you can control the fat content, and for this, a higher fat content is needed. If grinding yourself, Use pork shoulder with a bit of pork belly, use the coarse plate (the wagon wheel) on the first grind.
If using hog casings packed in salt, you will need to soak and rinse them following the suppliers instructions. If using dry hog casing, set them aside until needed, the just need a minute or two in water and can be used. You can also use collagen casings if you prefer.
Soak the glass noodles in hot water for about 30 minutes, drain and gently squeeze out the remaining water. Add the glass noodles to the ground pork and mix together.
Add the chopped mushrooms to the ground pork and mix together.
To a blender, add the galangal, lime leaves, garlic. Blend until well mixed.