I was at the Farmers' Market last week and I bought a stalk of brussels sprouts. It still had the top leaves (which look like a cross between cabbage and a HUGE brussels sprout).
For anyone who hasn't seen a brussels sprout stalk, this website link has a good picture (though mine was a much smaller variety).
I asked if the top leaves were edible too (they seemed a bit thick and perhaps tough).
The vendor said she wasn't sure, because they never ate them (but joked that their donkey absolutely loved them). She suggested I check online.
Which I did, and discovered they are edible and even found suggestions for using them (essentially using them like Kale).
So, I decided to roast the top leaves along with the brussels sprouts, and I discovered that I like the brussels sprout tops even better than the sprouts (which isn't a hard sell to me, because even though I've learned to like brussels sprouts they're not my absolute favorite, except roasted with a little more oil than I usually use for roasted veggies to get the edges really crisp).
WOW, the big leaves are better than kale chips, because they get crunchy edges, but hold their shape better (they don't just disintegrate into crumbs like kale tends to do).
The only problem I forsee is that they're so good, I want them all year round, but it's definitely a seasonal item with very limited availability. It's also a "trash" part that most vendors discard or use themselves (if only to feed their livestock).
I was really impressed though, and don't know why these aren't sold for human consumption more widely. You can buy turnip greens, why not brussels sprout tops (you probably can wherever brussels sprouts are more appreciated).
Anyway, I washed and dried the leaves, put them in a gallon sized ziploc bag tossed them with a couple tablespoons of oil and shook the bag to coat all the leaves (the bag was so full it took more than a tablespoon, which I use for most veggies). Then I threw in a couple tablespoons of ranch dressing mix powder (like the Hidden Valley Ranch packets, but I buy in bulk. One packet should be sufficient if you're using packets.
Then I roasted them at 425 degrees for about 30 minutes (until the leaves were crispy, but the stems were tender - very yummy).