Black Bean-Avocado Salad Stacks

herb salad:
1 cup cilantro
1 cup fresh dill
1 cup fresh basil
2 T. lemon juice
2 T. olive oil
1 T. whole-grain mustard

stacked vegetables:
1 t. olive oil
1/4 cup diced red bell pepper
1/4 cup diced celery
1 green onion, trimmed and thinly sliced
1 cup canned black beans, rinsed and drained
1/2 cup diced hearts of palm
1 avocado
1/2 cup frozen corn, thawed

herb salad: combine cilantro, dill, and basil. Coarsely chop 1/2 cup herb mixture and set aside. Whisk together lemon juice, oil and mustard in bowl. Toss chopped herbs with 21/2 T. lemon juice mixture.

Stacked vegetables: heat oil in skillet over medium. Add bell pepper, celery, and onion, and sauté 2 minutes, or until vegetables are softened. Toss with black beans, heart of palm, 1 T. chopped herbs and 1 T. lemon juice mixture. Season with salt and pepper.

Mash avocado in bowl. Stir in corn, remaining chopped herbs, and 11/2 T. lemon juice mixture.

To assemble: (use 4 inch metal ring mold or a clean 14 oz condensed milk can) place ring mold on salad plate. Fill with 1/3 avocado mixture using spoon to smooth. Top with 1/4 black bean mixture, then 1/4 herb salad. Lift off ring and repeat for remaining stacks.