Light Lungs and Liver

Rinse the offal and place it in a pot. Cover with water so that it submerges the meat, bring to a boil, and skim off the foam. Add the onion (peeled and halved), vinegar, bay leaf, cloves, and peppercorns, season with salt, and simmer over low heat for about an hour.

Remove any connective tissue and cut the meat into strips. Strain and reserve the broth.

Melt the butter in a large skillet, add the flour, and sauté while stirring until light brown. Add the prepared meat, stir to coat evenly with the flour mixture, and pour in about 500 ml of the reserved cooking broth. It is best to add the broth gradually, stirring and heating the contents each time to prevent lumps. You should end up with just enough sauce to completely coat the meat, but no more. Taste the sauce and adjust with salt, pepper, and perhaps a bit more vinegar if needed (the flavor should be distinctly tart). Cover and simmer over low heat for 10 minutes.