BLT Potato Salad

8 all-purpose potatoes (about 3 lbs)
6 strips bacon

Dressing:
1/2 cup mayonnaise (I like Miracle Whip)
1/2 cup sour cream
1/4 cup water
2 Tbsp Dijon mustard
1 tsp salt
1/2 tsp ground black pepper
1 cup chopped celery
1/2 cup sliced red onion
1/4 cup minced sweet gherkins
1 medium head romaine lettuce, cut crosswise in 1/2" wide strips
1 pint cherry tomatoes (halved)

Peel potatoes and cut in 1" pieces.  Put into a large saucepan with cold water to cover.  Bring to a boil over high heat.  Reduce heat and simmer 12 minutes or until firm-tender.  Drain and let cool slightly.

Meanwhile cook bacon in a skillet or microwave until crisp.  Cool, then cut in 1/2" pieces.  (Wrap and refrigerate at this point if making ahead.)

Whisk dressing ingredients in a large bowl until well blended.  Add warm potatoes, celery, red onion and sweet gherkins and mix gently.  Let cool.  (Cover and refrigerate at this point if making ahead.)

To serve:  Line a serving platter with romaine lettuce.  Top with potato salad.  Sprinkle with bacon and tomato halves.