Tonkotsu Chicken Broth

Bring a kettle full of water to a boil. Lay the wing tips and chicken bones in a clean sink, then pour the boiling water over the chicken.

Wash the chicken with cold water, scrubbing off any clumps of blood.

In a small saucepan, add the leeks, ginger and garlic, then cover with vegetable oil. Gently fry over medium low heat until the aromatics are dark brown, but not burnt (about 30-40 minutes).

Add the kombu, wingtips and bones to a pressure cooker and cover with 10 cups of water. Bring it to a boil uncovered, then skim off the scum that floats to the top. Continue skimming until you don't see any more scum. Remove the kombu and discard.

Drain the fried leeks, ginger and garlic and add them to the pressure cooker.

Pressure cook on high for 1 hour. Let the pressure naturally release.

Strain the liquid and squeeze the solids to extract as much liquid as possible. Pour the strained soup through an extra fine sieve (such as a tea strainer) into a clean container.

If you have more than 6 cups of liquid, boil it down to 6 cups, if you have less, add water to make it 6 cups.

Refrigerate or serve right away. If you refrigerated the stock, scrape off most of the excess fat, leaving some behind for texture and flavor.