Clean the hens: Pat the chicken dry with a paper towel.
Combine spices: Add 1/4 cup oil to liquid measuring cup. Then add in 2 teaspoons salt, 1 teaspoon paprika and 1 teaspoon garlic powder and 1 teaspoon black pepper. Add zest of 1 lemon and minced fresh rosemary if desired. Mix together.
Spice the hens: Rub 1/2 of the spice rub on each hen, coating the entire hen, including the cavity.
Prepare for baking: Tuck the wings behind the hen and tie the drumsticks with twine. Place the hens on the rack in a roasting pan or 9x13 dish. Add quartered onions and lemons if desired.
Bake: Bake for 50-60 minutes, or until the thickets part of the breast reaches 165°F.
Rest: Remove from oven and allow to rest for 5 - 10 minutes.
Cut and serve: Cut the hens in half to serve, or serve whole optionally garnished with rosemary.
Notes
Store any leftovers in the refrigerator in an airtight container for 3-4 days.