I love farro. It's a delicious, nutty, easy-to-use whole grain. I also love the panzanella (bread salad) of Tuscany. So this is my healthier, more substantial version of panzanella: I swap the bread out for whole-grain farro which makes the salad less of a pap with vegetables than the original. I haven’t included tomatoes here but if it is the season, I would certainly add them. If you don’t have purslane you could use a big bunch of leafy basil instead, using the whole leaves as a salad green.
Cook the farro in a large pot of salted water until tender but still with some bite, about 10 minutes. Drain and cool.
Peel and halve the onion, then vertically cut into very thin slices.
Meanwhile, peel the cucumber and slice into 1/4-inch-thick half-moons. Quarter the radishes. Trim and remove any large woody stems from the purslane.
Place the cucumbers and radishes on top of the onions and add the farro and purslane. Season with a little more salt and plenty of cracked black pepper. Drizzle with the olive oil, toss, and serve.