In a mixing bowl combine the hare, pork belly, and Cognac. Season with salt and pepper. Mix well, cover with plastic wrap and chill overnight. To make the sauce, heat the oil in a large saucepan and cook the onions, shallots, and carrots until softened, about 10 minutes. In a medium saucepan melt 4 tablespoons of butter over a moderate heat. Whisk in the flour and cook for 1 minute. Stir in the chicken stock and the cooked onions, shallots, and carrots. Season with salt and pepper. Bring to a boil, then reduce heat, cover, and simmer for 1 1/2 hours, skimming occasionally. Strain. Preheat the oven to 475F. Cut the caul fat into 12 individual squares. Form the meat mixture into 12 patties and wrap each patty in a piece of caul fat. Place the patties on an ungreased cookie sheet and bake until golden, about 30-35 minutes. Stir the crushed peppercorns and red currant jelly into the sauce and simmer for 10 minutes. Remove the pan from the heat and add the remaining butter, a little at a time, whisking between each addition.
