Preheat oven to 350F/180C. In a large deep skillet, add the olive oil and bring to medium heat. Add the onion, garlic and celery and cook stirring often until the veg is softened. Season with rosemary, thyme, fennel, sea salt and pepper.

Pour the vegetable broth into the skillet and mix to combine. Turn off heat and add the baguette cubes. Gently stir to mix the brothy liquid with the bread.

Transfer to a large casserole dish (8×11 inches) and cover with foil. Bake for 40 mins, then remove the foil and increase the heat to 400/200C. Bake for another 10 to 15 mins, until the top is crispy and golden.