Without getting too technical, cooked bacon would be safe for at least 4 hours or so but it would have to be cooked at least "medium" for lack of a better word.
The reason is due to something in food safety called water activity or Aw. This is a measure of how much "free water" a food has, that is water that is not tied up in other food molecules.
Bacteria need this free water to grow. The Aw scale is 0 to 1. Anything below .86 is considered safe at room temperature. Cooked bacon's Aw is less than .86, as the free water is driven out during cooking. Raw or undercooked bacon would not be safe.
The reason that you have seen bacon sitting out at the local eatery is because the health department knows about water activity. You will notice that the bacon has been pre-cooked to medium and then finished on order.
So your bacon may or may not be safe depending on how well you cooked it originally. I would guess safe, however, since my microwave always seems to overcook my bacon.
I hope this "saves you bacon"
Hey, someone had to say it