Add pork parts to large stock pot, cover with water, bring to a boil then drain water from pork & rinse bones. Add rinsed bones to pressure cooker & top with 5000g/5L water. Cook, high pressure for 80 mins.

Return broth & bones to large stock pot & bring to boil for 30 min until broth has taken on an opaque quality & has reduced by 25-30%. Strain out solids.

When finished, texture should be soft, but not shreddable. Allow to cool in liquid then wrap & refrigerate.

Add flour, salt, & baked soda to food processor. In separate container, mix food coloring into water. With processor running, stream in yellow water. Dough will be dry & pebbly. Allow ito sit for 30 min to hydrate. Press together into a mass. Cut into 4 strips then link together into 1 long belt. Roll flat & wide into a shape that fits through a pasta roller. I'm using the kitchen aid pasta attachment.

Feed dough through on the widest setting, fold in half & repeat. Reduce roller thickness, feed pasta through, & repeat several times until the dough turns into a more smooth, pasta looking sheet. Fold dough in half, increase roller thickness, & repeat several more times until you get a smooth sheet on #6 on the roller.

Cut this long sheet into 12"/30cm sheets then drop each through a spaghetti cutter (or hand cut). Measure into four, 5oz portions. Cover & refrigerate until ramen time.

Boil eggs 7 minutes then drain & transfer to ice bath. Once cooled, peel & move to a food storage bag with water, mirin, & soy sauce. Press out air & marinate for 4-24 hours.