I have synthesized 3 of these so far, but I have been reluctant to use them. My key jobs are non-melee, and so I would not be able to take adequate advantage of their benefits.
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I have now tested this on a Galka SAM56/THF28.
Much to the horror of those nearby, he stripped down to his skivvies to test this food. The results were:
STR+4 VIT+2 AGI+1 INT-2 Base attack went up 29 from 108 to 137. Base defense went up from 102 to 103.
Note that the attributes seem to be identical to the regular version, Dhalmel Stew.
At this time, we are unable to time the food. However, given that the normal version is a non-stacking three-hour food, this dish should in theory last four or five hours.
I'm going to start making the stews on a regular basis to give out to my parties' DDs, and will keep the HQ versions to provide for my LS when we do multiple Garrison runs.