Pat the chicken dry with paper towels and season it generously with salt, pepper, and the rosemary. Heat 2 tablespoons of olive oil over medium heat in a large Dutch oven and brown the chicken pieces in batches until nicely browned all over, about 5 to 7 minutes per batch. Transfer the browned chicken pieces to a plate and set aside.
Lower the heat to medium-low and add the garlic, saffron, fennel seeds, tomato puree, chicken stock, white wine, Pernod, 2 teaspoons salt, and 1 teaspoon of pepper to the pot. Sir and scrape up any browned bits on the bottom, and simmer for 30 to 40 minutes, until the garlic is very tender, stirring occasionally.
Meanwhile, preheat the oven to 300 degrees.
Carefully pour the sauce into the bowl of a food processor fitted with the steel blade. Puree until smooth. Return the sauce to the Dutch oven and add the sliced potatoes and browned chicken pieces with their juices. Stir carefully.
Cover the pot and bake for 45 to 55 minutes, until the potatoes are tender and the chicken is done. Check the seasonings and add small extra amount of stock if you want a thinner sauce. Serve hot in shallow bowls with slices of crusty bread.