Put the raisins into a cup or bowl and pour the 125ml boiling water over them.Put 675ml water in a pan for the polenta and set it on to boil.Heat the oil in a heavy-based frying pan of about 28ch diameter (that has a lid) and cook the pancetta (or other) cubes for 3-5 minutes, stirring every now and again, then add the minced garlic and chopped shallott and cook for another 3-5 minutes, until the pancetta is bronzed and the shallot soft.Stir in the cumin (not Italian, but Venice was the hub of the spice trade so I allow its inauthentic addition) then add the raisins with their soaking water and let it bubble up before tipping in the borlotti beans and their liquid (but see introduction above if your bean gloop is unusable)Bring to the boil, then add the shredded radicchio and, once the stew starts bubbling again, turn off the heat, put on the lid, and get on with the polenta.Add salt (to taste) to the now bubbling polenta water, then stir in the polenta, pouring it into the pan in a steady but gentle stream, and cook till smooth and thickened. I use more than the usual ratio of water to polenta here, as I want the finished polenta creamy not set. Once it is cooked, take the pan off the heat and beat in the Parmesan and butter, seasoning to taste. Decant into a warmed serving bowl.Check the bean stew seasoning, then bring it to the table with the golden polenta.