Ramen

A Sacramento ramen restaurant seems to use "Paitan Ramen soup EX" as their tonkatsu ramen soup base:

http://www.somifoods.com/products/paitan-ramen-soup-ex/
Product DescriptionThis authentic tonkotsu ramen base blends high-quality tonkotsu broth with vegetables and other ingredients.
How to useMake the ramen base by combining 1 part of this product with 9 parts hot water or broth.
Packaging
60 fl. oz. (1.8 L) x 6

The web site lists the following recipe. So simple!

TONKATSU RAMEN
Ingredients

• Noodles – 1 bunch
• Cha-shu (roasted pork) – 2-3 pieces
• Green onions – A small amount
• Bamboo shoots – A small amount

Cooking Directions
Pour 1 oz. of Paitan and 9 oz. of hot water or broth into a bowl. Add boiled noodles and desired toppings.

Add as desired

• Boiled egg
• Red ginger
• Kikurage
• Dried seaweed