Step #3 Heat cheddar cheese, salt, onion, & Worcestershire sauce over low heat/flame, stirring constantly, mustard, until cheese is melted; remove this from heat.
Step #4 Beat eggs in large bowl until foamy; beat cheese mixture in slowly.
Step #5 Pour into pie shell.
Step #6 Cook uncovered in 325F degree oven just until set, about 25 mins.
Step #7 Cut tomatoes into thin slices.
Step #8 Overlap slices around outer edge of pie to form a wreath.
Step #9 Sprinkle top with salt, pepper, & parmesan cheese.