Funny that you chose mango! That was also the food that caused me my greatest cooking injury. I grew up in the Philippines, and we used to put a butter knife into the seed of a whole, ripe mango and freeze it. Later, we could peel off the skin and have a really wonderful popsicle. One afternoon, I finished putting a knife into mine, and my sister asked if I could do hers, as well. Sure! Only, the butter knife slipped, and, unbelievably, cut my thumb deeply enough to require stitches. (Consequently, the stitches were administered without novocaine-- not a great first-stitch experience for an eight year old!)

It's also funny that you pick mango because the skins of mangoes have an irritant in them similar to poison ivy. I know a few people who love mango but cannot eat it because it makes their lips puff up. Which is a real shame, because mangoes are delicious.

Yep, Mango.

The skin contains urushiol, which is the chemical in poison ivy and poison sumac. I can't touch the stuff. If someone else dices it for me however...

Mmmmm...mango.

i think i remember having a terrible time shucking oysters. i find any type of slicing is dangerous when the knife isn't sharp enough - like chopping onions.

I struggled most with live dungeness crab. But, it was totally worthwhile. The food came out absolutely delicious! http://7th-taste.com/2010/12/26/wok-fried-dungeness-crab-with-tamarind-sauce-pinot-gris/

Butter Nut Squash.....My mother and I still laugh about the time we made soup for Thanksgiving...it's took us hours and multiple kitchen utensils to cut thru that "darn" thing.

Large sweet potatoes or yams. They are super hard to cut through. Also I have a fear of eggplant now because I sliced off the tip of my finger once....

It's usually user error for me - I always try to cut cherry tomatoes and strawberries in my hand, and have gotten a few cuts from that. Pretty dumb, but I'm too lazy to get a cutting board out! I've also cut myself with a regular old teaspoon while trying to scoop out cookie dough that had been chilling in the fridge. So basically any food and any utensil can be deadly in my hands!

I haven't had much practice with mangoes since the one time I sliced some up for a mango tiramisu (delicious by the way) my face puffed up and I was covered in hives. For a whole week I was a monster. I scared small children. No more mango for me.

Dicing onion with a dull knife, and sweet potatoes due to the hard centers when they're raw.

Definitely big winter squashes, kabocha particularly! I came VERY close to slicing myself up making a kabocha and ginger soup this last winter.

I've since learned a good trick: stab it a bunch and microwave it to soften it up a bit before cutting it up.

Of all things, carrots... Peeling them is a surprisingly dangerous endeavor for me. Though that might just be my peeler...

I find the CHAYOTE one of the most difficult vegetable to peel and slice.

Tiny hot peppers, particularly seranos and habanero. Serranos have a hard skin that requires a sharp knife, but I'm always holding them delicately to avoid getting the heat on my fingers.
Ive had 3 nasty serrano cuts... and I still haven't learned.

Butternut squash, pumpkin, yep. Those are hard to cut.

Avocado. I've had knife slips more often while slicing avocados than any other fruit.

Anything I slice with a mandoline! Finally got myself one of those cut proof gloves! ;)

Turnips! I have now officially enlisted my dad with a hammer and a chef's knife to cut up those bad boys for mashing during Thanksgiving. He's a pro.

Pretty much anything; my boyfriend is convinced I'm going to cut my fingers off due to my poor knife skills. But I second the melon vote. I've had several cantelope cuts. Winter squash is always scary.

For all the people who have issues with slicing hard winter squash, I found the solution by roasting any hard squash whole, and then taking the skin off once it's completely cooked. Not only it makes the job very easy, but it gives the squash a delicious flavor. Then dump in a pot with water to finish it off as a soup.

My biggest knife mishap was with frozen latkes that I was trying to separate. How smart of me. I did think about turning the blade away from me, but forgot about the tip of the paring knife... I still have a scar on my left index finger...

I'm not bad with a knife. But I have suffered some bad cuts at the hand of the box blade on aluminum foil or plastic wrap. *shudder*

Pumpkins and butternut squash, definitely. It also doesn't help when you really need to actually sharpen those knives...

Mangoes, though, I've never had any problem with, either in cutting myself or being irritated by them!

CARROTS. I can cut through melons and squash and potatoes but carrots are like rocks! I know there is something else I have a hard time with, but can't remember. I cut myself slicing a bagel once, no big deal. I cut strawberries in my hand all the time too. The key is to use the right knife. A duller, smaller knife works fine for strawberries, etc. I use a semi-sharp butchers knife for melons. I use a small, shaaarp knife for everything else. But those carrots! Nothing makes me feel safe with 'em!

The dorsal fins on some fish can be razor sharp. Oysters, watermelons, squash.

Sweet potatoes. If I'm cutting a large one up it's like trying to cut through a brick.

Hot chillies!

I actually burned myself (fingers and eyes) pretty badly on these suckers, a while back. It was really painful. And I don't even have particularly sensitive skin. I'm never handling them again without kitchen gloves!

It's a running joke now, but I had a guacamole accident before I learned the proper way to get the seed out. Hint: it's not stabbing directly down at the pit with a paring knife.

I'm more of a burn-prone person in the kitchen, but I'm really nervous around sweet potatoes and squashes, which I LOVE.

A friend recently stabbed himself through the hand and had to have emergency surgery as he was cracking open a coconut. Such a friendly fruit, who would have thought?

To save your fingers when dismembering a winter squash - put it in a sturdy bag and throw it on the floor/patio. It will smash into parts and save your fingers.

Watermelon is a toughie if it's cold and beaded with sweat to try and cut in half!

My big one that I watch roll on the floor every time and drives me a little nutty is green onions or carrots. No matter where or how I cut at least a few pieces find their way on the floor!

For me...carrots - always get nicked peeling them, and have somehow managed to cut off the end of a fingernail or two trying to dice them...

@jmorri26 Simple tip: Unless you're leaving the rind on for wedges of watermelon, cut the ends off so you have a flat surface, stand the watermelon up, then cut the skin away in slivers until the watermelon is skinned and ready to be cut in chunks- SO much faster and easier than hacking it into chunks then trying to cut off the flesh.

Mangoes. Absolutely. I've MASTERED avocados though. The trick is getting them ripe enough so after you cut it in half, the skin just peels away, nice as you'd like.

I haven't had any knife accidents (yet), because I take way too long to cut my ingredients. But I'm a real klutz when it comes to grating cheeses and carrots. I always grate the skin off my fingers. Ouch.

Not sure why you try to cut the pit out of the mango. Usually I eat it by shaving off slices until you get to the hard part, holding it how you'd hold a potato you were peeling. Pretty safe and controlled. I wouldnt try to cut it up like an apple and try to core it.

For a less messy (and safer) mango experience I find Roy de Groot's solution to be entertaining:

Grab a mango that is firm, but ripe and without brown spots. Knead the fruit gently with your hands, without splitting the flesh, for 3-4 minutes. Take the end where the stalk was attached and make a small hole. You should be able to suck the mango juice and flesh through the small hole.

I once bought a small pumpkin to make a soup but it was impossible to cut through it! After almost losing one of my fingers, I threw it away and gave up. Now I only buy it if it is already peeled and cubed!

Rutabaga! I'm a master of avocado, competent with mango (like Joey C I shave the mango off the pit), I've never come across a squash or melon I couldn't chop, but for the life of me I can't tame a rutabaga. Luckily for me, my local grocery store offers pre-chopped rutabaga (unfortunately it's much more expensive than buying whole)!

Mangos are my most dreaded prep food too, but because I am allergic to their skin! I have to wear gloves and swap cutting boards after removing the peel. I almost wish I didn't love them so much, then I wouldn't ever have to peel them again!

Mangos, fish, and overly frozen ice cream.