In a small bowl, combine mayo, creamy horseradish, salt, pepper and paprika. Place in refrigerator until ready to build the sandwiches.
In a frying pan over medium high heat, add bacon. Cook until crispy and remove to a paper towel covered plate. (Cook in batches if needed).
Toast bread to desired. Strongly recommend putting two slices in one slot (if your toast allows).
Spread both insides of bread with horseradish mayo. Layer with roast beef, two slices of provolone, red onions, microgreens and 3 slices of bacon. Add top bread and add two long toothpicks and then cut in half.