Special equipment: Butcher's twine
Preheat the oven to 425 degrees F. Mix together the fennel seed, salt, oregano, onion powder and smoked paprika in a small bowl. Set aside.
Mix together the cornbread and milk in a medium bowl. Allow the mixture to soak for 10 minutes. Stir in the sausage, Pecorino and chili paste. Use your hands to mix well.
Lay the turkey breasts skin-sides down on a cutting board so that they are open like a book. Pat half the stuffing onto each skinless side, leaving a 1/2-inch border, then close each half so the skin sides are up. Tie each turkey breast tightly with 4 pieces of butcher's twine about 1 1/2 to 2 inches apart. Rub the seasoning mix all over the turkey.
Lay the bread on a rimmed baking sheet and drizzle with 2 tablespoons of the olive oil. Place the turkey breasts skin-sides up on the bread and drizzle the remaining 4 tablespoons olive oil over the tops. Roast 30 minutes, then reduce the heat to 375 degrees F and continue to roast until the skin is brown and crisp and an instant-read thermometer reads 160 degrees F, about 40 minutes more. Allow the turkey to rest for 10 minutes before slicing and serving.
To make a quick sauce, bring 2 cups of low-sodium chicken broth to a simmer over medium heat. In a small bowl make a slurry by mixing 5 teaspoons of cornstarch with 5 teaspoons of water. Whisk the slurry into the simmering broth. Season with 1/4 teaspoon smoked paprika, 1/4 teaspoon oregano and 1/4 teaspoon kosher salt.