Choose crisp, white bean sprouts that have the beans attached. Rinse the sprouts, pat them dry with paper towels and refrigerate them for up to 3 days in a plastic bag along with a paper towel to absorb excess water; rinse and dry them again before using.
Place 2 sandwiches in a 12x8-inch (2-quart) microwave-safe dish lined with a double layer of microwave-safe paper towels. Microwave on HIGH for 2 to 3 minutes or until the ham is hot and the cheese is melted. Repeat with the remaining sandwiches.