8 ounces green beans, rinsed, ends trimmed, and cut in 1-inch pieces

3 pounds Yukon Gold or thin-skinned potatoes, scrubbed and cut into 1-inch chunks

2 tablespoons olive oil

2 tablespoons brown sugar

1 sweet onion such as Maui, Vidalia, or Oso (about 8 oz.), peeled and sliced crosswise 1 inch thick

2 fully cooked sausages (about 10 oz. total)

1/4 cup mayonnaise

1 1/2 tablespoons Dijon mustard

1/4 cup balsamic vinegar

1/3 cup pitted black olives, coarsely chopped

1/4 cup minced parsley

Salt and pepper

 

In a 6- to 8-quart pan over high heat, bring 3 quarts water to a boil. Add beans and cook until crisp-tender, 1 to 2 minutes. Remove beans from water with a slotted spoon or strainer and rinse under cold running water until cool. Return water to a boil. Add potatoes, reduce heat as necessary to maintain a simmer, and cook until potatoes are tender when pierced, 15 to 20 minutes. Drain. Meanwhile, in a small bowl, mix olive oil and brown sugar. Place onion slices and sausages on a baking sheet and brush generously with brown sugar mixture. Broil 6 inches from heat until onions and sausages are lightly browned and onions are tender when pierced, 8 to 10 minutes. Let stand until cool enough to handle. Coarsely chop onion. Slice sausages 1/2 inch thick. In a large bowl, combine beans, potatoes, onion, sausages, mayonnaise, mustard, vinegar, olives, and parsley. Mix gently to coat, adding salt and pepper to taste. Serve warm, or chill until cold, about 2 hours.