With the addition of a grilled chicken breast, this unusual appetizer salad would be a great main course. The fruit on its own makes a wonderful little "chutney" to serve alongside a piece of grilled chicken or swordfish or to scatter across the top of focaccia before baking. The dried fruit adds richness, so don't leave it out. In the autumn and winter you can use figs, apples, pears, or persimmons in place of the grapes, while in summer you can use plums, apricots and peaches.
Separate the radicchio into leaves, saving the heart for another use. Tear into bite size pieces and add to the dried fruit mixture along with the spinach. Toss well. Divide among 4 plates and top with the prosciutto, if using. Scatter the pine nuts over the top.