Preheat a large sauté pan or stock pot over medium heat. Add the olive oil and heat until shimmering. Add the onions and season with a pinch of salt. Cook, stirring regularly, until the onions are soft and translucent and have reduced in volume by half, around 20 minutes. Add the butter and cook, stirring regularly, until the onions are golden brown and caramelized. Add the garlic and cook, stirring, 1 minute.

Add the Kettle & Fire Classic Beef Bone Broth, thyme, bay leaves and pepper. Bring the soup to a gentle simmer, cover with a lid, reduce the heat to low and cook 10-15 minutes for the flavours to come together.

Meanwhile, preheat oven to 450F. Place the bread on a sheet pan and lightly drizzle with olive oil. Transfer to oven and toast until golden brown, around 10 minutes, flipping halfway.

Place oven-safe bowls or ramekins onto a sheet pan to catch any overflow. Ladle in the soup, top with croutons and cheese. Switch the oven to broil, place the soup on the top rack of the oven and cook until the cheese is melted and bubbling, around 2 minutes. Remove from oven and let cool 5 minutes before serving.