Scotland
Master of Malt
Made with the world's hottest chilli, Naga Jolokia, we reckon these bitters probably tip the scale at around about 250,000 Scoville units.
These Single-Varietal bitters are made using only three ingredients; the spirit (High-proof 8 year old Bourbon), Naga Chillies, and natural bittering agents.
Use (incredibly) sparingly in a Bloody Mary - one drop will almost certainly be enough. Master of Malt accepts no responsibility arising from the use (or misuse) of this product. We'd advise you just to throw it away. It's probably for the best.

In a moment of stupidity I tried these bitters on the back of my hand at a bar. They blew my head off. I couldn't taste anything for half an hour. I think they might be somewhat over-kill and more of a novelty as they were so spicy you'd need so little in any one drink. Still, an impressive potion.