Bacon

1. Preheat oven to 250 degrees.
2. Add the bacon to a large skillet and cook on medium heat on the stove until crispy.
3. Once crispy, remove it and place it on a plate lined with a paper towel. Let it cool. Set aside for later.

White Sauce

1. While the bacon is cooking, start the white sauce.
2. In a larger saucepan add in butter and melt over medium low heat. Add in the flour and whisk together with the butter. Cook for two minutes - the flour tastes out. This is the base for the roux sauce to thicken.
3. Reduce the heat to low, slowly add in milk 1/2 cup at a time, and whisk until thick and combined. Whisk generously to ensure all clumps are out and that the mixture doesn't scorch on the bottom of the pan. 
4. Add in the parmesan cheese and spices. Whisk until the mixture has thickened. Once it is thick, remove from the heat or keep on a warm setting until needed.

Butter Sauce

1. While the bacon and white sauce are cooking, start this as well.
2. Add the butter and the rest of the ingredients into a small saucepan on medium-low on the stove. Let melt completely, whisking to stir everything together.
3. Keep on the stove until needed

Assembly

1. Slice Hawaiian rolls in half and break each piece apart. Line the bottom of the rolls in a 9x13 dish.
2. Place a small amount of mayo on the bottom of each roll and spread to the edge. It doesn't take much, just enough to cover the bottom.
3. Fold 1 slice of turkey onto each sandwich.
4. Break the bacon into halves or thirds, adding 1-2 pieces on top of the turkey.
5. Add some tomatoes on top.
6. Spoon a generous amount of white sauce over top each roll. 1-2 tablespoons for each roll. You will have leftover sauce (perfect for dipping sandwiches in!).
7. Sprinkle remaining parmesan cheese over top.
8. Place the tops of the rolls back on and brush each top with the butter mixture. Be generous with this.
9. Place in the oven and cook for 20 minutes.
10. Remove and serve immediately while hot!