Steam green beans in a 6-quart pot of boiling salted water, uncovered, until just tender, 4-6 minutes. Drain the beans, pat dry with a paper towel and place in a serving bowl. Allow to cool.
In a medium mixing bowl, whisk together the Blue Cheese Herb Mustard, garlic, salt, pepper, and red wine vinegar. Whisk until combined.
Slowly drizzle the extra virgin olive oil into the mustard mixture, whisking continuously to form an emulsified vinaigrette.
Toss the green beans with enough vinaigrette to coat the green beans, green onions and parsley. Garnish with bacon, if desired.