Add the potatoes to a large pot and cover by 1-inch with cold water. Add 1 tablespoon of salt and bring to a boil over high heat. Cook until fork tender, 12 to 15 minutes and drain
well. Let cool slightly then slice into 1/4-inch thick pieces and add to a large serving bowl.
Stir together the remaining ingredients in a medium bowl. Pour the mixture over the warm potatoes and mix gently until combined, mashing the potatoes slightly. Season again with salt and pepper, to taste, before serving.