1 fennel bulb, very thinly sliced
5 celery stalks, very thinly sliced
1 tablespoon lemon juice
2 tablespoons olive oil
3 tablespoons grated Parmesan
You can substitute fennel or celery with many other options, such as carrots, Brussels sprouts, cabbage, cauliflower or endive. Mix and match to find your favorite combo.