Given the background description of some cooking related query, summarize the question into a title

Example Input: Today I sauteed some onions and in some spots they were caramelizing nicely while in others they were slightly burnt.Anyone knows who could be the possible culprit? I am betting on the frying pan but I wish to get some second opinion before buying something fancy.
Example Output: What is the reason my veggies cook unevenly?

Example Input: Many recipes call for first bringing milk up to boil.I normally boil 1 quart (1 litre) of milk in a 3-quart stainless steel heavy bottomed pan:use low heatkeep scraping the bottom of the pan every 1-2 minute Milk comes to a boil in about 40-45 minutesIn spite of my carefully watching the milk, at the end, when I pour of the milk, I see a "crust" form on the pan. This makes cleaning up a pain.Further, it is hard to constantly watch and scrape the milk every 1-2 minutes.Is there a more convenient way to bring milk up to a boil?Looking for:Unattended, fool-proof methodEasy clean-up at the end.Yes, I am aware of this other question:Quickest, and safest way, to bring milk to boil?However, my question is a bit different.
Example Output: Can I boil milk unattended (and still keep the pan clean)?

Example Input: To which temperature could I safely heat my cast-iron pan on the stove, without any contents? I don't want to re-season it afterwards. Afterwards, I'd just let the pan cool off in room temperature. The base is ~0.5 cm thick.
Example Output:
How much could I safely heat a content-less cast-iron pan?