Slice liver into 1/4 - 1/2 in thick pieces and soak in lemon juice or milk for a few hours before cooking. Rinse and pat dry and coat in flour/salt and pepper. Over medium high heat in a cast iron pan in bacon fat or lard, cook the liver for a few minutes each side until firm. Remove and keep warm.
In a sauce pan heat vinegars, figs and stock until reduced in half. Whisk in flour until sauce gets to desired thickness. Salt to taste.
Serve liver with sauce, and top with bacon and onions. This dish is rich and goes well with fresh bread to soak up extra sauce.