Preheat the oven to 250 degrees F.
the pears from top to bottom, leaving the stem intact, and lay them in a lidded oven-proof dish just large enough to hold them. Bring the wine
to a boil, cover the pears
with the liquid, and transfer to the oven. Bake until very tender, 4 to 5 hours, turning now and again.
Gently remove the pears to a serving bowl with a slotted spoon. Boil the liquid rapidly until reduced to syrup, about 20 minutes. Pour the syrup over the pears and reserve at room temperature for several hours, or cover and refrigerate until about an hour before serving. Serve with whipped cream which you've sweetened with a little sugar and flavored with Cognac