1Halve and core apple, leave skin on. Cut into 1/2" thick slices, cut slices into matchsticks, 1" long. Do the same with potatoes. Cut pepperoni and cheese into same-size pieces. Shred prosciutto. Combine apple, meats & cheese in large bowl.
2Prepare Creamy Mustard Dressing:
Whisk cream in small bowl until it begins to thicken. Add vinegar, mustard, green onion, salt & pepper; whisk until well combined.
3Add dressing to salad ingredients in bowl; toss to coat well.
4Arrange shredded lettuce on serving platter. Mound salad on top. Sprinkle with toasted almonds. Serve.