Of all the dark roast coffees that I've tried (and there have been many; I've brewed dark roasts almost exclusively over the past few years), the monsooned Malabar is my favorite. It's gives a really nice, very full-bodied cup without overwhelming acidity, which I think translates to a cup that's full but not overpowering in its taste. With some of the darker roasts with higher acidities, I almost can't pick out what flavors or notes I'm supposed to be getting. I feel like it just ends up a dark, muddy brew that tastes strongly of coffee. However, with the Malabar, I can have a nice cup and get the chocolate and "earthy" flavors out of it. With this, you can have your cup and taste it, too.
Anyway, you can find some details about the monsooned Malabar here. I think it's a really interesting process, particularly given that the coffee was monsooned to begin with in order to replicate the weathering process that used to occur during the months-long shipping journey by sea that coffee used to require in the 19th century. If you read around enough on it you'll see some roasteries mention using it in espresso blends, but I think it's generally good enough to stand on its own.
For this brew, I've done something a little different and tried it with a French press. I was surprised at the lack of oil in my cup, because this is a very oily roast (it generates quite a bit of static cling inside the grinder) and I suspected the lack of paper filtration would provide an "oil slick" in my cup. However, that wasn't at all the case. More exploration is needed to see if the behavior continues.
Grind size: most coarse (16/16)
Bloom time: 30s, then stirred the grounds for five seconds before capping without plunging
Steep time: 4 minutes
Water temperature: started brewing at 93°C
Ground coffee mass: 40g
Brewing water mass: 600g
Water to grounds ratio: 15:1
The results: I included some of my tasting findings above, and the marked increased in suspended particulates definitely gave the cup more of a punch. Some resources suggest a 10:1 ratio, but I thought that would have been way too much for the starting cup of a darker brew. Furthermore, I generally disagree with the target ratios offered by some of the more popular online roasteries and breweries (higher ratios, more coffee used, more coffee ordered...), finding them a little too strong for my tastes--this is particularly true for my Chemex methods, which you'll find don't use enough grounds by the Blue Bottle recommendations. YMMV, but I thought the 15:1 ratio for a dark roast French press brew is a respectable place to start. In the future, targets for exploration will include an increase in the ratio.
Update 4/26/2016: I've been playing with brewing this in the Chemex recently, and I've found that the ratio needs to be tweaked a bit to not taste so overwhelmingly like burned beans. I think I've hit the proper ratio with the following attributes (and unchanged referring to the settings I used in the rundown above), but the biggest change I've made is to reduce the water temperature by 10 degrees. It's not much, but reducing the temperature and making the adjustments to the water to grounds ratio both worked to change the flavor profile. I found that each attribute changed individually didn't do enough; the effects were additive.
Grind size: 12/16
Bloom time: unchanged
Water temperature: Started brewing at 88°C
Ground coffee mass: 40g
Brewing water mass: 700g
Water to grounds ratio: 17.5:1