Summer Bean Salad with Lemony Dressing

Adapted from a recipe by Tyler Florence, Eat This Book

1 lb. mixed summer beans (sugar snap, green beans, etc.)
2 shallots, finely chopped
1/2 cup walnut pieces toasted
1 handful flat leaf parsley and/or mint
dressing
1 Tablespoon grainy mustard
1/2 teaspoon sugar
juice of one lemon
1/3 cup olive oil
1/4 cup plain yogurt
salt and fresh ground pepper

Heat a pot of salted water to a boil and cook beans 3-5 minutes
until crisp tender. Strain and quickly place in a bowl of cold water.
Drain well. Transfer beans to a mixing bowl and add shallots,
walnuts and parsley. Whisk together dressing ingredients and
toss with bean mixture to coat.