1 tablespoons lemon juice
1/4 teaspoon fine sea salt
 Freshly ground black pepper
1/8 cup extra-virgin olive oil
1 large or 2 small fennel bulb(s), thinly sliced
1 Granny Smith apple, halved and cored, thinly sliced or cubed
(you can also use whatever apple you have on hand)
1 celery stalk, thinly sliced
1/4 cup fennel fronds or parsley leaves, roughly chopped
1/4 cup toasted walnuts
1 ½ ounces Parmesan cheese, shaved (about 2/3 cup)

1. In a small bowl, whisk together lemon juice, salt and pepper. Slowly drizzle in the olive oil, and whisk briskly until dressing is emulsified. Taste and add more lemon juice or salt if needed.
2. Place the walnuts in a dry pan and heat over medium-low heat, stirring occasionally. Keep an eye on it so the oil in the nuts does not burn. After 3-5 minutes, remove from heat and dice when cool. Set aside.
3. In a large bowl, combine the apple, celery, fennel, and walnuts.
4. Toss the fennel, apple, walnuts, and celery with the dressing. Fold in fennel fronds or parsley, and top with Parmesan cheese just before serving.
   
   NOTE: Dressing can be made the day before serving, and stored in the refrigerator. Toss with salad ingredients up to 1 hour before serving.

*optional substitutions:
almonds or pecans for walnuts;
gorgonzola or blue cheese for the Parmesan cheese;
mint or basil for part or all of the parsley