This is a traditional pasta sauce from the area where I am from. Originally the walnuts were boiled for about 5 minutes and then peeled. I find it unecessary as the modern blenders can whisk all the ingredients very finely. Plus I find that that thin skin gives the sauce just a tiny bit of a bitter kick which I consider an extra. Last but not least you save half an hour time and it makes this sauce even quicker than a simple tomato sauce. Well let's start.
Put the white loaf slices in a small bowl with all the milk. Put the walnuts into the blender bowl, put the soaked loaf on the top (keep the milk aside), then the olive oil, add salt, pepper, marjoram and the garlic clove. Slowly add milk until you get a thick cream... Believe it or not... You just have to add the parmesan cheese and it's ready!!!