- 1 teaspoon Dijon style mustard
- 2 tablespoons lemon juice
- 1 tablespoon red wine vinegar or cider vinegar
- ¼ teaspoon salt
- ⅛ teaspoon black pepper
- ⅓ cup olive oil
- 5 ounces baby spinach
- 1 head Boston lettuce or ½ head Romaine lettuce
- 2 cucumbers, peeled and thinly sliced
- ½ fennel bulb, optional
- Make the vinaigrette: In a small bowl, whisk together the mustard, lemon juice, vinegar, salt, and pepper. Slowly, add the olive oil, whisking constantly until the mixture is smooth. Set the dressing aside.
- Make the salad: Gently tear the lettuce into 2-inch pieces. Put the lettuce, spinach, and sliced cucumbers into a serving bowl. Cut the fennel bulb, if using, into long thin slivers and add them to the salad. Just before serving, pour the vinaigrette over the salad and toss until the salad is evenly coated. Serve immediately.