never tried this myself, but most likely they'll just steam themselves and not get much of a Maillard reaction going unless you get the pan RIPPING hot (and then good luck unsticking them...)

honestly I would try chucking them in the toaster oven on some parchment paper, on the broil setting to get a light char

As an aside, a thin coating of vegetable oil in the pan is going to be a pretty negligible day intake.

I'll grill (on a charcoal grill) golf ball sized tomatoes whole with no problem. Without oil, the peel will do some serious sticking, but the tomato flesh will be fine.

I grill vegetables often. Put a cast iron pan in you grill that way you get all the smoke and related flavors but you can easily manage the cooking.

I have never grilled sliced tomatoes but I have grill grape tomatoes and they are tasty.

only one way to find out! but i would expect it might stick to the pan real bad.

Try it and see - cooking is meant to be a learning experience!

That said, a little fat used just right (even distribution helps - mix it up in a bowl beforehand) can go a long way. Tomatoes are plenty healthy, and a little oil won't ruin that any more than a little dressing won't ruin a salad's healthiness.

The best dishes have a good balance of fat, salt, acid and heat. If you're cooking a bunch of tomatoes, I'd use a small amount of olive oil, salt or soy sauce, maybe a small dash of balsamic if you want an extra dimension of acid (the tomato supplies its own too), and garlic powder (or skip the salt and use garlic salt) for a little heat.

So far, I've also always added a splash of olive oil, but I cannot imagine it ruining the tomatoes when you don't, since they mostly just cook in a pan. They have too much moisture to really grill (unless you leave them for far too long).

I cut them in half instead of slicing. They'll keep together easier that way.

Oven baked is also an easy way to heat tomatoes.

maybe, depends on the pan and depends on the temperature depends on the ripeness of the tomatos.

i'm assuming you are not using green tomatos or cherry tomatos or some other brand.

note: i do not like tomatos at all. they give me unbelievable heartburn/acid reflux/non-spicy firebreathing/reverse montezuma's or something equally awful.

now that you know that, i'll also mention i've cooked a lot.

i suggest trying parchment paper (look for non stick kind but it might be okay otherwise) and an oven. if they aren't too squishy, they shouldn't stick and you can avoid the oil.

another alternative, which takes much, much longer, is using a food dehydrator. (warning: never put oil, or anything similar to oil, in a food dehydrator. it turns it into a house incinerator.) just put the tomatos in the dehydrator, turn it on, wait.

this also is how to turn jalepenos into chipotles. also poblanos into anchos. probably a bunch of other things change names when dried out too, those are the two i remember.

Well what kind of pan are you going to use? And do people really cook tomatoes in lard wtf lol

Are you a bot?

It sounds like you may want to get an air fryer. I've not tried pan frying tomatoes without oil but I don't think frying pans are designed for oil-less cooking. You could also go for stuff that's more like a soup or stew or curry if you want hot food with not too much (or no) oil.

You can absolutely fry tomatoes, half, sliced, or whole, without fat. And tomatoes have enough water not to stick or burn. (You may want to watch and adjust the temperature)

You may argue that's booling or steaming, not grilling, but the outcome will be fine.

Do you like the taste of burnt tomatoes? Go for it, it you like a char. I'd bread the tomatoes and fry them.

I think salt and pepper grilling is way worse than just ala natural.

You'll probably break them, and even if you don't they will taste a bit like tomato sauce. High risk of getting them stuck to the pan.

Lol @ all the fryiers here. Grilled tomatoes are regularly cooked on charcoal grills, do you think they somehow add oil there?

Slices can be grilled in a grill pan, but they easily break down when you try to pick them up. A ceramic non-stick can help there. The easiest way is to cut them in half and grill them on their skin, you should choose a thicker-skinned variant of tomato too.