Reducing fresh tomatoes for sauce - pan, heat, etc.

I use a large stockpot that is stainless steel. Do not use bare aluminum, the tomatoes will react with it.

make it simple and dont add different things so that it doesnt overpower whatever ucook in it. make t simple maybe some grlic basil and tomatos maye some tom. juice and reduce. medium heat should be fine.

I agree with Mary - no aluminium, it will give on unususl and not nice taste - but the bigger the pot, the better.

I agree with Skatz as well, keep it simple.  You can always add other things in later when you are cooking the dish you want.

FWIW, I do not flavor my canned tomato sauces. Nothing in the jars but tomato and a little salt. Reason: This leaves my options open for when I'm actually cooking. The jarred stuff then serves as the platform for whatever tomato-based sauce or soup I'm working on.

I start by quartering the tomatoes. These go in a pot and are cooked down just until soft. I then pass them through a food mill to remove the seeds and skins. The remaining "puree" is then cooked down to the consistency I want. I tend to do my boiling-down over low heat.

Pot choice is determined by size. That is, it depends on how many tomatoes I'm working with. Generally speaking, a pot that is wider than it is high works best for reducing liquids. And, as others have noted, you want a non-reactive pot: no aluminum or copper. And, for this process, cast iron isn't the best choice either.

All I add for seasoning is salt and pepper, as mentioned it keeps the tomato sauce usable in more recipes.

I would say I do it more out of habit than anything else. In addition to straight reductions, I often put up things that have a heavy sugar content; such as apple butter and tomato jam. Low and slow, with lots of stirring, is the only way to avoid scorching.

With tomatoes there's another reason. More than any other product I've worked with, tomatoes form mini-volcanoes as they cook down. The harder the boil (which is a function of the amount of heat) the higher and further these eruptions throw hot sauce.