This is a modern(relatively speaking) version of a Medieval Germanic recipe. While living in Germany, I first tried these unusual cold pizza-style open face sandwiches at a fair in Bonn while celebrating the "Rhine in Flames." Clara12 has a recipe posted on Recipezaar for homemade Krauterfladenbrot recipe #61947 ,the herbed flatbreads used as the "crust" in this recipe(which I have tried and used in this recipe successfully). You may also use any herb flecked soft, doughy flatbread that you have available - they should be rounds the size of a pita bread. Heck - you could probably get away with using an uncut pita(in which case use the whole pita as your crust for each -don't split) if that's all you have available - I'd go for honey wheat flavor, if so. Please try to use sweet onions in this as regular onions can be a little too strong - you will be eating the onions raw, so it is up to you how much oniony sharpness you prefer. Try to cut the onions as wafer thin as possible and then into slivers. Please use real bacon and fresh herbs - although there is a brand(Hormel) of real bacon that comes precrumbled in a bottle that may use(not Bacon Bits). Measurements are estimates - season these to your liking. Cook time is chilling time for the onion sauce - there is no actual cooking involved.