To spatchcock the hens, using sharp kitchen or butchering scissors to cut out the spine of the bird. Insert the scissors at the top of the cavity and cut along one side of the spine, separating it from the rest of the back. Repeat for the other side and discard the spine. With the bird breast side-down on the cutting board, press the back apart so it lays as flat as possible. Using a sharp knife, score the sternum between the breast. Once scored, press down with your hands on each breast so that the bird lays even more flat. Repeat for the other hen.

Toss the brussels sprouts and beets with 2 tablespoons of the olive oil. Spread them out in a rimmed baking sheet then sprinkle the top with 1 teaspoon fine sea salt and a sprinkling of black pepper.

To season the hens, work half of the butter under the skin (but over the muscle) on the breast and leg. Repeat for the other hen. Rub the top of each bird with the remaining olive oil. Sprinkle with the rest of the sea salt, garlic powder, pepper, and fresh rosemary.

Place the flattened (spatchcock) hens on top of the vegetables breast side-up. Bake at 375 for 50 minutes, or until the tops of the hens are starting to turn golden brown. Let rest for about 5 minutes, garnish with additional rosemary (if desired), and enjoy!