1 tablespoon walnut oil
Kosher salt
1 small shallot, minced
¼ cup fresh lemon juice
1 tablespoon Champagne vinegar
½ cup extra-virgin olive oil
Freshly ground pepper
1 bunch French Breakfast radish, thinly sliced
1 red spring onion, thinly sliced
4 heads Little Gem lettuce, leaves torn or coarsely chopped
¼ cup freshly grated Pecorino Romano cheese, plus more for serving