My brother has an outdoor stove that he has used in the past to make maple syrup. It has a wood firebox on the bottom which heats up the sap. The sap is held in container that sets into the unit for boiling the water out of the sap. This is the recommended way to make syrup because it saves on propane costs and also gives the syrup a smokey flavor. I hope to get another batch boiled down this weekend using his stove. That might finally be the end of our production for the season.
The pictures below are plated French toast covered in syrup and maple glazed pork tenderloin. The glass in the background is not Sherry, it's a glass of Glen Echo's own homemade Maple Syrup
I've attached a couple of videos from You Tube which shows the making of maple syrup in Wisconsin. A little larger scale operation than Glen Echo.