Would be nice if maple trees had a function, and I figure this was the intended purpose of maple trees existing in the first place.
Make a tap out of a metal nugget, right click it onto a maple tree, right click a bucket onto the tap.
10l of sap boils down to 0.2l of syrup (from what I understand that ratio is fairly accurate irl) on a cauldron, which can be further boiled into a few mg of Maple Sugar.
Peppering food increases FEP gains, so Sugar would increase Energy gains from food when applied to it? Seems about right to me