01 - Place all vegetable scraps, optional potato, and fresh vegetables into a large stockpot.
02 - Incorporate bay leaves, parsley, thyme, black peppercorns, garlic, salt, and apple cider vinegar or lemon juice if using.
03 - Pour in the cold water and stir gently to combine all ingredients evenly.
04 - Heat over high until boiling, then reduce heat to maintain a gentle simmer.
05 - During the first 10 minutes of simmering, skim off any foam or impurities rising to the surface.
06 - Let simmer uncovered for one hour, stirring occasionally.
07 - Take the pot off the heat and allow the broth to cool slightly.
08 - Strain the liquid through a fine-mesh sieve or cheesecloth into a large bowl or container, discarding solids.
09 - Taste the broth and adjust salt or acidity as desired.
10 - Use immediately or refrigerate for up to 5 days; alternatively, freeze for up to 3 months.