Collect veggie scraps in a large pot.

Add onion, garlic, bay leaf, peppercorns, vinegar, oregano/thyme.

Cover with just enough water to cover veggies. Add Parmesan rind if using.

Bring to boil then reduce to simmer. Simmer, uncovered for 45–60 minutes.

Let cool for 30 minutes then strain through fine-mesh sieve or cheesecloth.

Store in fridge for 4 days or freeze in convenient portion sizes for 6 months.

Save veggie scraps in a freezer bag or container until you have enough to fill a pot.

Make it hands-off: add everything to a slow cooker and simmer on low for 6-8 hours.

Speed things up: use an instant pot at high pressure for 20-30 minutes, followed by a natural release.

Build extra flavour by adding mushrooms or mushroom powder, miso paste, nutritional yeast, dried seaweed, roasted garlic or a splash of soy sauce.