Bierstacheln, which means beer spike or beer sting, is a German tradition that involves inserting a poker heated to about 600 degrees celsius (!) into a dark beer for a few seconds. This not only warms the beer but apparently creates a spontaneous maillard reaction that caramelizes unfermented sugar, changing the flavor and creating a frothy head. The process was invented by blacksmiths to keep their beer warm in winter when it was too cold to drink.
For their seventh birthday, Austin's Lazarus Brewing offered up a range of their St Pete's oak aged imperial stouts for poking. I tried the version called Mexican Hot Chocolate with Wartryx Hot Peppers (10% ABV) and it tasted amazing, gently warmed with a toasty marshmallow aroma and flavor. I sometimes struggle with beers that strong but the poking made it very drinkable.