1. Preheat the oven to 350°. Toast the walnuts on a pie plate for 7 minutes, or until lightly browned. Let cool and coarsely chop.
2. In a small heatproof bowl, soak the currants in hot water until softened, about 10 minutes; drain.
3. In a small bowl, whisk the cream with the mustard, Pernod, vinegar and garlic and season with salt and pepper.
4. In a large bowl, combine the frisée with the onion and currants. Add 1/4 cup of the dressing and toss to coat. Transfer the salad to a platter. Put the ham in the same bowl, toss gently with the remaining dressing and arrange over the salad. Sprinkle the walnuts over the top and serve.
Make Ahead: The recipe can be prepared through Step 3 a day ahead. The walnuts and currants can stand, covered, at room temperature. The dressing can be refrigerated.