To make the dressing, crush the sea salt, rosemary, garlic, and sugar into a paste with a mortar and pestle (or smash it all together with a knife); work in the crème fraîche and vinegar, taste and adjust with a bit of pepper and more salt if needed.
Combine the celery, apples, salad greens, and most of the nuts in a large serving bowl with half of the dressing. Toss well, adding more dressing until it is to your liking. Finish with the remaining nuts, and any torn celery leaves.
adapted from Heidi Swanson’s 101cookbooks.com
*Pink Pearls have a very short season, if you’ve missed it—try swapping in other heirloom apple varieties. 2 large, crisp apples should do the trick.