1. Take a medium sized stoneware bowl with lid and place it in a large glass bowl to make a solar cooker and place it on a reflector.
2. Bunch up the herbs and stuff up the cavity in the hen along with the garlic.
3. Sprinkle salt and freshly ground pepper on the hen.
4. Pour in the olive oil and massage well on the hen.
5. Place it in the stoneware bowl and cover it with lid. Place the entire thing in the glass bowl and cover it.
6. Let the whole thing stand in the sun and cook for about 3 hours and 20 minutes with an outside temperature of about 58 degrees Farenheit.
7. Insert a food thermometer and check the internal temperature. It should be more than 165 degrees Farenheit.
8. Place the chicken on a plate and reserve the stock.
9. Cook the stock on stove top and thicken it with the cornflour.
10. Cut the chicken into pieces and serve it with the gravy.