Sweet Potato Edamame Salad - cooking recipe

Ingredients

5 large white potatoes
2 large sweet potatoes
2 small yams
1 1/2 cups edamame
1 small onion, diced
3 tablespoons mustard
3 tablespoons vinegar
1 teaspoon balsamic vinegar
2 tablespoons extra virgin olive oil
1 tablespoon salt
1 tablespoon ground black pepper

Preparation

Boil potatoes and big sweet potatoes for about 25 minutes -- you want to just be able to get your fork in them, but not so soft that you would/could mash them.
Shock potatoes in ice-cold water -- set aside until you can easily handle them.
Boil yams (the small, American sweet potatoes -- not the true \"yam\") for about 7 minutes -- you want to just be able to get your fork in them, but not so soft that you would/could mash them.
Shock potatoes in ice-cold water -- set aside until you can easily handle them.
Steam Edamame until cooked (5 mins).
Shock Edamame in ice-cold water -- set aside until you can easily handle them.
Whisk together Mustard, Vinegars, EVOO, Salt and Pepper in a small bowl. Feel free to use your favorite mustard or vinegar (I use a spicy whiskey mustard and some lingonberry infused apple-cider vinegar) -- this is your dressing, it should be thick, but somewhat viscous so you can easily mix into your salad.
Cut white potatoes into 2 inch cubes (more or less), cut the sweet potatoes slightly smaller, and slice the yams thinly, dice onion finely.
Mix dressing into potatoes and onions, add edamame, and mix again -- chill for 2 hours, and eat.