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

Q: Many a recipe or package instructs: 'cook uncovered' without stating a reason. As a general matter, is this to protect me from boilover, or does it have some more subtle purpose?

A: When a recipe says, 'simmer uncovered', what's the issue?
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Q: Recently, I observed that there is some brown slimy stuff on the underside of my plates. I don't know what they are or how they form. I tried removing it with a tooth pick, but was too hard to come off. Does anyone know what this is? How can it be cleaned?

A: What is this slimy coloured stuff growing in my plates?
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Q: I brew coffee using a french press. After I've pressed it, how can I make it chill fast?I've tried pouring it into a wider container (larger surface area) and putting it in the freezer. This is not optimal since I don't want to thaw the contents in the freezer. Also, this takes some time and risks spilling the coffee.When it is cold enough I put some ice cubes in a drinking thermos, pour in the coffee, close the lid and shake it. This part of the process works well because the ice "only" transfers the cold to the coffee and not the surroundings. I guess I could use crushed ice instead for greater effect?Is there a better/quicker way of making iced coffee?

A:
How can I chill ice coffee quickly?
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