Heat the oil over medium heat in a pot. Add the onion, carrot, celery and garlic; sauté until the onions start to soften. Season with salt and pepper.
Add the broth, thyme, bay leaves, and sage. Stir and bring to a simmer with a partially covered lid, for about 15 to 20 minutes to build flavor. Remove the thyme sprigs and bay leaves (very important to remove the bay leaves before serving to prevent hazard if ingested). Stir in the peas. Season with salt and pepper to taste
Ladle into bowls and serve with crackers. Garnish with parsley.