Peanut brittle | Bootstrap molasses | Bitter chocolate | Baking spices | Burnt brown sugar

Molasses | Dark caramel sauce | Barrel char | Dry oak | Fudge 

Clove | Cinnamon | Chocolate malt balls | Black pepper | Heavy seasoned oak 

There’s no stopping Denver’s Mile High Spirits quest to release the biggest and baddest HAZMAT bourbon ever. They seem to have an endless supply of 140+ proof bourbon, so much so that they even have a category for it on their website. 

Last year, we reviewed their 7 year, 142 proof single barrel bourbon and called it "instantly memorable.” Ultra high proof bourbons tend to do that. The company returns this year with an 8 year, 143.5 proof single barrel bourbon, and it's even bigger and badder than last year. But is that a good thing?

This year’s edition’s slight uptick in proof definitely gets in the way of the bourbon’s flavors, which tends to be a balancing act many high proof bourbons have to deal with. The extra year of aging, though, brings out even more oak, particularly dry seasoned oak, and it’s dominating. The company’s ultra-high proof bourbons typically don’t feature many fruit notes and instead double down on big, robust flavors of molasses, brown sugar, caramel, and oak. It results in a homogeneous flavor profile with little contrast. This 8 Year Single Barrel Bourbon reminds me a lot of the early batches of Stagg Jr., where the high proof was heavy-handed. 

Anyone interested in ultra-high proof bourbon should expect this degree of boldness, but the extra year of aging shows signs that it might be time to cut it off. Though this is just one single barrel and variations occur from barrel to barrel, the degree the oak plays in this barrel is pushing its limits. Though anyone into heavy oak or double oaked bourbons will likely love the oak here, compared to last year’s 7 year HAZMAT proof, the previous release offers breathing room for its flavors, and was a better bourbon because of it. 

The bourbon in review is from barrel #xxx.