1. Prepare Butternut Croutons, and set aside.
2. Preheat oven to 450°. Season each hen cavity with 1/2 teaspoon salt and 1/4 teaspoon pepper, and insert 1 clementine quarter into each.
3. Pull back breast skin of each hen gently, and insert 1 sage leaf. Replace skin, and use a presoaked wooden pick to secure skin to meat. Tuck wing tips under each hen, and tie legs together using butcher's twine.
4. Arrange hens, tail to tail in 2 rows, on a rimmed baking sheet, making sure wing tips stay tucked. Rub hens with butter, and season with remaining 1 1/2 teaspoons salt and remaining 1/2 teaspoon pepper.
5. Roast hens at 450° on middle oven rack 45 to 50 minutes or until hens are golden brown and reach an internal temperature of 160°. Transfer hens to a rack set over a platter, and cover loosely with heavy-duty aluminum foil. Allow hens to rest 5 minutes, and serve with warm Butternut Croutons.