In a food processor, blend the garlic, parsley, oil, lemon juice, and spices until you have a nice pasty marinade.
Place the Cornish hens in a thick ziploc bag or bowl.
Spoon the marinade over the Cornish hens.
Let marinate overnight.
When ready to bake, place the potatoes and chicken stock in a 9×13 pan or oven-to-table dish, cover tightly and bake for one hour on 350 degrees Fahrenheit.
After the potatoes have baked for the hour, raise the oven temperature to 400 degrees Fahrenheit.
Remove the Cornish hens from the marinade.
Place over the potatoes together with the shallots.
Bake at 400 degrees Fahrenheit for one hour, uncovered.