Brussel Sprouts are maligned for one single reason.
They have the largest concentration of elemental Sulphur in any edible plant.
Since Sulphur is very low on the periodic table compared to Carbon (but still an organic element), if you overcook Brussel Sprouts the Sulphur will manifest in both smell and taste. The overpowering odor of rotting eggs combined with the bitter taste us God Emperor fearing carbon based lifeforms attribute to the foul xeno, Sulphur based life will ruin any dish these alien plants grace. Unless you prepare and present properly.
The trick to cooking Brussel Sprouts is actually two tricks.
Trick one, remove the outer layer after cooking. This will remove the Sulphur smell which puts most people off. Trick two is adding a powerful flavor component Iike balsamic vinegar and bacon to overpower the bitter Sulphur taste.
Do those two things and you have a super vegetable. Just don't tell the commisar what's in it. And never feed it to an inquisitor.