Collards Potato Salad with Mustard Dressing

2 lbs. Red Dog Farm Potatoes, scrubbed
1 bunch Red Dog Farm Collards, coarse stems discarded and leaves cut into 1-inch pieces (sub stir-fry mix)
2 tablespoons Dijon-style mustard
2 tablespoons red-wine vinegar
1/3 cup olive oil
6 slices of bacon, cooked until crisp, drained, and crumbled
3 tablespoons thinly sliced scallion (or Shallot)

In a kettle combine the potatoes with enough water to cover them by 2 inches, bring the water to a boil, and simmer the potatoes 15 to 20 minutes, or until they are tender. Transfer the potatoes with a slotted spoon to a colander, reserving the cooking liquid, and in the reserved cooking liquid boil the collards, stirring occasionally, for 10 minutes. Drain the collards in a sieve, refresh them under cold water, and squeeze them dry in a kitchen towel. In a bowl whisk together the mustard, the vinegar, and salt and pepper to taste, add the oil in a stream, whisking, and whisk the dressing until it emulsified. Quarter the potatoes (or more if they are large) and add them to the dressing. Add the collards, pulling them apart to separate the leaves, the bacon, and the scallion and toss the salad well.