1. Pat the Cornish hens with paper towels to dry them. Then, combine the dry rub ingredients and generously apply them to the hens with your fingers. Apply the rubs to the inside cavity as well.
2. Set the oven to 425F and arrange the onion, garlic, thyme, rosemary, and half of the lemon slices in the baking pan. Next, place the hens on the herb bed, and drizzle with olive oil.
3. Bake the hens in the oven for 50minutes to one hour, or until the internal temperature reads 165F at the thickest breast.  Then, set them down to rest for 20 minutes. Save the pan juices for garnish.
4. Use a cleaver or very sharp long knife to cut from the middle into two halves. Place the blade at the breast and steadily force it down with controlled slicing moves till you slice through.
5. Serve each half with an herb garnish and a drizzle of the pan juices.

For more instructions, click on this video recipe.