Preheat large pot on medium heat and add olive oil. Then add onion, carrots, celery and garlic. Saute for 5 minutes, stirring occasionally.
Then add veggie scraps, fresh herbs, bay leaves and cold water to almost the top of the pot. Cover with a lid and bring to a boil, then reduce heat to low and simmer gently for 45 minutes. The longer broth simmers, the more flavorful it is.
Season broth with salt and pepper to taste, I like to start with 1 teaspoon salt and 1/2 teaspoon pepper. It depends what you will use it for. Then strain broth through a large fine mesh strainer over a large bowl.
Using a funnel, divide vegetable broth between large Mason jars or airtight containers and let cool to room temperature.
Notes
Store:Refrigerate chicken broth for up to 4 days or freeze for up to 3 months.