Step 1

Whisk together the first 7 ingredients in a bowl. Add salt and black pepper to taste. Adjust acidity and mustard level as desired.

Step 2

Place a steamer rack into a large saucepan. Fill the saucepan with water up to the bottom of the steamer rack. Bring to a boil.

Step 3

Place the beans on the steamer rack, cover, and steam for 4-5 minutes or until crisp-tender and still bright green.

Step 4

Transfer the beans to a mixing bowl and season with a pinch of salt. Let cool for 4-5 minutes.

Step 5

Drizzle with the vinaigrette as desired and toss. (You may not need all of it; reserve the remainder for another use, such as a green salad or a chicken marinade.)

Step 6

Transfer to a serving platter. Top with walnuts and parsley. Serve immediately.