- 2 tablespoons Dijon mustard
- 1 tablespoon best-quality red wine vinegar
- 1/2 small garlic clove, finely grated
- Kosher salt, freshly ground pepper
- 1/4 cup olive oil
- 2 small bunches watercress, tough stems trimmed (about 10 cups)
- Whisk mustard, vinegar, and garlic in a medium bowl; season with salt and pepper, then gradually stream in oil, whisking constantly. Whisk until dressing is emulsified and thick.
- Add watercress to dressing, season with more salt and pepper, and gently toss until watercress is evenly coated (you want to be careful not to bruise or wilt greens when tossing, so use a light hand). Pile salad lightly onto plates.