Preheat oven to 375°F. Place a rack in a roasting pan and lightly grease or line it with foil for easy cleanup.
Prepare the herb mixture: Combine olive oil (or butter), rosemary, thyme, sage, garlic, salt, pepper, paprika, and lemon zest in a small bowl. Stir to form a paste.
Season the turkey: Pat the turkey breast dry with paper towels. Gently loosen the skin and rub half of the herb mixture underneath. Spread the rest evenly over the surface.
Assemble for roasting: Place lemon halves and onion quarters in the bottom of the roasting pan. Set the turkey breast on top, skin side up. Pour chicken broth (or wine) into the pan.