Melt the butter or fat in a heavy bottom saucepan over medium heat. Add the bay leaf, caraway seeds and the prepped onion or shallots, sautéing for 5 – 6 minutes until the onion is transparent. Add a pinch of salt, then dust the onions with the flour, stirring to make a roux. Cook the roux for 3 – 4 minutes, stirring continuously to prevent the flour from burning. Switching to a whisk, slowly pour in the beer, followed by the cream. Whisk to combine, making sure there are no lumps of roux. Bring the mixture to a simmer and adjust the heat to maintain a gentle simmer. Add the peppercorns, cloves and nutmeg. Whisk occasionally over the next 30 minutes as the flour flavor cooks out of the sauce.