I brewed something last fall with friends, and the recipe was somewhat off-the-cuff. I wasn't super happy with the results. We were aiming for a Belgian Tripel, but weren't careful in selecting our grains and ended up with something between a Triple and a Quad. It is a bit more malt-forward than a Tripel, but not as dark as most of the Quads I have had. It also had a pound or more of Belgian candy sugar which left quite a bit of residual sweetness despite finishing at about 12% ABV.
I don't really like the end result, and the beer has been kegged in my fridge for about the last 10 months. The beer doesn't really have any off-flavors, I just don't care for the combination of sweetness and maltiness. I'm considering trying to sour the beer with lactobacillus or doing an additional fermentation with brett. I love sour beers, and was thinking this might be a good opportunity to salvage this beer and turn it into something I'm excited about. If it turns out undrinkable I won't be heart-broken.
Does anyone have any suggestions for me? I'm not sure what strain of bugs to use, and for how long, and whether I will need to add fruit or something to provide additional food for another fermentation. I'm assuming this will affect the alcohol content as well, but I'm not sure to what extent.