Pound pheasant with mallet, then pull the outer membrane off the skin. (Pheasant skin is not like chicken skin, but has a covering film.)
Using the point of a knife or a larding needle, make incisions in fleshy parts of the pheasant, and insert the little bacon sticks. Salt pheasant inside and outside.
Wrap the sheets of salt pork fat tightly around the pheasant. Place it in a covered roasting pan and bake in a 450°F. oven for 10 minutes.
Remove the pan from the oven and arrange the sliced onion and sour cream on the bird. Again cover the roasting pan and return it to the oven. Reduce heat to 375°F. and roast for an additional 35 minutes.