5 cups mixed lettuce or romaine
1 cup sliced hearts of palm
1 cup sliced mushrooms
1 tablespoon Kosher for Passover mustard
1 tablespoon hot water
1 lemon, juiced
1/3 cup extra-virgin olive oil
1 heaping tablespoon mayonnaise
1/2 teaspoon sugar
Kosher salt and freshly ground black pepper
Place lettuce, hearts of palm and mushrooms in a large bowl.
In a mason jar, combine the mustard, water, lemon juice, oil, mayonnaise, sugar, salt, and pepper. Put the cap on and shake vigorously to emulsify. Drizzle the vinaigrette over the greens and toss well to coat. Serve immediately. Store any remaining vinaigrette in the jar in the refrigerator.