1. In large saucepan cook onion in hot butter over medium heat until tender. Stir in potatoes, cider, thyme, salt, and cayenne pepper. Bring to boiling; reduce heat. Simmer, covered, 15 minutes. Add chopped apple; simmer, covered, 5 minutes or until potatoes are tender. In small bowl combine milk and flour; stir into soup. Cook and stir until bubbly. Slowly add cheese, whisking until cheese is melted.
2. Divide soup among serving dishes; top with apple slices and peppercorns. Makes 4 to 6 side-dish servings