Unlike most other lettuces, escarole and radicchio are hearty enough to chop ahead of time. Tom Valenti uses only tender, inner escarole leaves for this salad, reserving the tougher outer leaves for soups. Terrific Green Salads
In a large bowl, whisk the vinegar with the thyme, oregano, garlic and sugar. Whisk in the oil and season with salt and pepper. Add the escarole, radicchio and fennel and toss well. Serve right away.
The dressing can be refrigerated for up to 2 days.