They're not cooked right.
Mr. mm used to hate Brussel Sprouts.
My recipe is to get fresh ones, cut them in half.
Slice an onion. Chop up some bacon in chunks.
Fry the bacon. Remove from pan and add the Brussel sprouts and fry for 10 mins stirring occasionally. Add the sliced onions at about the 8 minute mark and fry until preferred doneness.
Add the bacon back in, mix well, and serve hot.
Blue cheese crumbles and raspberries on top for the last one minute in high convection heat.