Cook the stock: Put all the ingredients in a 6-quart Instant Pot-style multicooker or pressure cooker. Add 6 ½ cups (1.5L) water. Lock the lid in place. Bring to high pressure, adjust the heat to maintain pressure (if needed), and cook for 45 minutes. Unplug the Instant Pot or remove the cooker from the heat, depressurize naturally for 20 to 25 minutes, and then manually release the residual pressure.
Strain and use: Unlock the cooker and wait for any bubbling to subside, about 5 minutes. Using a metal ladle, remove most of the fat on top, leaving some for flavor. (Or, remove the fat after straining and chilling the stock, when it’s easier.) Using a slotted spoon, remove the large solids. Position a fine mesh strainer over a medium or large saucepan (line the strainer with muslin for super-clear stock and easy straining) and ladle or pour the stock through. Use the stock immediately, or transfer to airtight containers and refrigerate for up to 3 days or freeze for up to 3 months.