I’m betting X-men because the stripey-haired gal can assume anyone else’s super powers, so all she’d have to do is grab a really good chili cook by the hand and bleed off her cooking powers.
Batman is well known whenn it comes to preparation.
I’m gonna say the JLA. The X-Men would have a good pot going, but then Gambit would screw it all up by putting crawfish and celery in it, thinking it was gumbo.
But making great chili isn’t just about preparation. All the cramming and gadets don’t help in the end - you need a good chili cook, and I say Wolverine is it. After all, his super-nose lets him know his cookin’s going just right.
I’ve heard the Firey Phoenix 50,000 Alarm Chili is good enough to destroy galaxies.
X-Men, claws down. Good chili requires a lot of chopping, and great chili should make your eyes bleed. Wolverine does the cooking, and Professor X telepathically convinces everybody that it is the best chili they have ever tasted. If time is a factor in the cookoff, Cyclops can blast the chili pot into high gear. 
My gut feeling is that even though it’s irrelevant to the recipe, Aquaman would insist that there would be some kind of fish in the Justice League chili, which would be a really bad thing.
GI Joe.
Nobody beats Roadblock’s chili.
But isn’t that like feeding a hamburger to a cow? I’d think the opposite.
Here’s another reason why I think the X-Men would fail at this task. I think they operate as a team much better than the JLA, who can get away with just powering through opponents. As a team, everyone wants to get involved. Beast is going to be in the middle of things, multitasking with all four limbs, Collossus is just going to get in the way being “helpful”, Wolvie is going to cut the beef too small in an overzealous attempt to outdo whatever it is that Cyclops is doing, etc. And as everyone knows, too many cooks spoil the broth.
Actually, Aquaman would insist no fish. Gambit would try to add okra (I don’t mind celery in my mirepoix, but okra is Lucifer’s lunch); but Rogue would stop him and shove that okra where the sun don’t shine, and then make some kick-ass cornbread for a side. Both Professor X and the Martian Manhunter would manipulate the signal your tastebuds send to your brain - that’s a tie so we’ll exclude it. Batman would have the best recipe, and the best plan for execution, and all the best kitchen tools and gadgets. But good chili needs soul and he has none.
Therefore, I’ll have to agree with Max Carnage. I like my chili to make my tongue run out of my body, and Jean has Bea beat in that department. Plus, with Wolive handling prop work, it will be done faster.
Still the JLA. Even if we exclude Batman, who if he knew ahead of time that he had to make chili, would indisputably make the best chili. Nothing about the X-Men indicates they are capable of doing more than eating Chef Boyardi ravioli cold and straight from the can.
Gotta go with the JLA. I mean, they’d have access to any kind of spice they need - Firestorm’s a human spice rack. Throw in Red Tornado for stirring, and you’ve got a winner!
As opposed to the Flash?!?
A strike against the JLA: Batman has been used to Alfred’s cooking lo these many years, and we all know how good English cooking is… I dare say that Bruce’s sense of taste has been destroyed, as has his ability to identify good food.
Let’s break it down into categories.
Recipes
X-Men: Influenced by Rogue and Gambit, good southerners who know what chili should be.
JLA: Batman (see above).
Advantage: X-Men
Ingredients
X-Men: typically seen shopping for groceries (Ult. X-Men-Ult. War). Usually forget a few items and have to go back.
JLA: Flash and Supes can get fresh ingredients straight from each item’s native soil.
Advantage: JLA
Prep Work
X-Men: Wolverine’s claws, Beast and his multitasking, Colossus and his “helping”.
JLA: Flash and Supes
Advantage: JLA
"Soul"
X-Men: Rogue/Gambit
JLA: I dunno, Firestorm? Someone with more thorough info may need to take this one.
Advantage: X-Men
Misc.
X-Men: Slight disposition for infighting. Too many cooks.
JLA: Slight possibility of Amazo, Luthor or Brainiac sabatoging the pot of chili. Bruce may want to severely reduce the level of spice to “protect” Robin.
Advantage: X-Men
And he comes with his own knives.
Have you ever seen the Flash use a knife? I don’t want the special ingredient to be speed-force infused blood. As for Superman, he’d need an adamantium chopping board and table, and adamantium doesn’t exist in the DCU.
Hey, as a counterpoint, any chili Wolverine makes that stings his tastebuds is gonna be lethal to most other folks.
sigh You all just have to be beaten over the head with it, don’t you? JLA, if for no other reason than Green Arrow is a member and will do the cooking.
Now go about your business and let this thread die in peace.
Ummm…but what makes the JLA special? Nothing about them indicates they are capable of doing more than eating Chef Boyardi ravioli cold and straight from the can.
Oh, and silenus, Cyclopes can’t do that. His eye beams are not heat, they aer jsut force. Like getting hit with a mack truck, not a bomb.
Green Arrow is an established chili lover and cook. Among the X-men, on the other hand, all we have is Wolverine and his ravioli-opening claws.
But he’s also a spoiled, rich white boy, surrounded by a bunch of other corn-fed white boys. They probably can’t handle true heat. What he thinks is hot, true chili lovers would classify as mild.
Rogue and Gambit and Wolverine - I bet they could handle true heat! Ororo - definitely. Jean Grey - only as Phoenix. Cyclops would melt faster than Iceman though. Nightcrawler and Beast would combust, Colossus would corrode from the inside-out.