Begin by cutting the bread into bite-sized chunks and put them in a large bowl. In a separate bowl mix together the cream, milk, sour cream, eggs, sugar, vanilla, and spices.
Pour the batter over the bread and gently fold it together. Then fold in the blueberries.
Tear off large sheets of foil and spray them with cooking spray. Scoop a serving size of the french toast onto each sheet of foil and then tightly fold them.
Place them over a fire that has reduced down to hot coals (rather than shooting flames) for about 20-30 minutes depending on the heat of the fire. After about 20 minutes, check for doneness by opening one of the foil packets to see if the middle has set up. The bottom and edges should be a nice golden brown color. If not cooked through, reseal and return to fire for a few more minutes.