1. Preheat the oven to 350°F.

2. Cut the fennel bulbs into quarters. Remove and discard the root ends.

3. In an ovenproof braising pan, heat 4 tablespoons of the butter over medium heat. Add the fennel and onion and cook for about 2 minutes, or until the onion is softened.

4. Grate the zest from 1 orange and reserve. Cut all 3 of the oranges in half and squeeze the juice into the pan. Add the Pernod, ignite it to burn off the alcohol, then bring the liquid to a brisk simmer, scraping the bottom of the pan with a wooden spoon to deglaze. Simmer until the liquid reduces by half, then add the chicken stock. Season to taste with salt and pepper.

5. Stir in the remaining 4 tablespoons of butter. When incorporated, cover the pan and bake for about 20 minutes, or until the fennel is tender.

6. Transfer to a serving bowl. Season to taste with salt and pepper. Garnish with the reserved orange zest and fennel fronds and serve.