What happens when you roast a lemon? It morphs from a fruit that's impossibly sour, to one that's improbably sweet. Squeeze the juice from that sweet lemon and blend it with bright, fresh herbs and fruity olive oil, and you create a salad dressing that's a little bit magical. For this simple salad, I sliced a seedless English cucumber into paper-thin slices on the mandoline, drizzled it with the dressing, and let it sit for 15 minutes so some of the dressing seeped into the cucumber. Try this with zucchini, or beets, or thin slices of boiled potato, or nectarines. I had some dressing left over, and slathered it on grilled salmon -- and yes, it was perfect.