In a medium saucepan over high heat, bring the water to a boil. Add the bay leaf, sage, thyme, garlic, and salt. Simmer gently for 40 minutes. Use a slotted spooon to remove the bay and sage leaves, and discard. Taste the broth and add more salt if needed. Remove from heat.
Separate the yolk from one of the eggs, reserving the white for another use. In a medium bowl, whisk the yolk with the other egg, Parmesan cheese, and pepper until creamy. While whisking, slowly drizzle in the olive oil. While continuing to whisk, slowly (slowly!) add a large ladleful of broth. Pour the contents of the bowl into the garlic broth and whisk continuously until it thickens to the consistency of cream.
Serve in bowl, ladled over the torn bread and drizzled with olive oil.