Potato Salad with Fennel and Mustardy Dressing
Dana Treat Original
Serves 6-8

Spring onions look like giant scallions.  You will want to use the bulb part only (the part that looks like an onion) and discard the greens.  You could substitute a large sweet onion (like Walla Walla or Vidalia) instead.  Be sure to buy a fennel that has some of the fronds attached (the green dill like looking top) because you will stir some of the chopped fronds into the finished salad.  Make sure to dress the salad when the potatoes are warm.  They will absorb the dressing beautifully.  Finally, potato salads, like pasta salads, taste best room temperature.  You can store the salad for a day or so in the fridge but take it out about an hour before you want to serve it.

For the dressing:
2 tbsp. plain yogurt
2 tbsp. mayonnaise
2 tbsp. Dijon mustard
2 tbsp. whole grain mustard
2 tbsp. horseradish
Juice of ½ a lemon
Pinch of salt and freshly ground black pepper

For the salad:
2½ pounds new potatoes, scrubbed and cut into large bite-size chunks
Olive oil
3 spring onions, bulb part only, chopped
1 large fennel, inner core removed, chopped
2 tbsp. fresh parsley, chopped
4 stalks of celery, thinly sliced
2 tbsp. chopped fennel fronds

Make the dressing:
Mix together the first six ingredients in a bowl.  Taste and add salt and pepper to your liking.

Make the salad:
Preheat the oven to 375ºF.  Lay the potato chunks on a large baking sheet and drizzle with 2-3 tablespoons of olive oil.  Shower with salt and a few grinds of pepper.  (Potatoes need salt!)  Place in the oven and bake for 20-25 minutes without disturbing them.  A paring knife should easily pierce them.  Remove from the oven and let cool slightly.

Meanwhile, place a large sauté pan over medium heat.  Drizzle in just enough olive oil to coat the bottom, then add the onions and fennel and a large pinch of salt.  Cook, stirring occasionally, for about 5 minutes, then add the parsley.  Continue to cook until the vegetables are very soft and brown in places, about 10 more minutes.  Scrape the contents of the pan into a large bowl.

Transfer the still quite warm potatoes to the bowl along with the celery.  Spoon out about five tablespoons of the dressing into the bowl and, using a spatula, mix together gently.  Add the fennel fronds and mix again.  Taste for salt and pepper and additional dressing if desired.