- 1 1/2 teaspoons mustard seeds
- 2 tablespoons apple cider vinegar
- 1 tablespoon fresh lemon juice
- 1 teaspoon Dijon mustard
- 1/3 cup olive oil
- 2 bunches watercress, thick stems trimmed (about 8 cups)
- 2 small heads of Belgian endive, cut lengthwise into 1/4-inch-wide strips
- 2 bunches radishes, trimmed, sliced
- Stir mustard seeds in small dry skillet over medium heat until seeds begin to pop, about 3 minutes. Transfer to small bowl; cool. Add vinegar, lemon juice, and mustard to mustard seeds. Gradually whisk in oil. Season dressing with salt and pepper.
- Toss watercress, endive, and radishes in bowl with enough dressing to coat.