Many recipes call for ingredients that are normally stored cold to be at room temperature at the time of use. One example is a cake recipe, which often calls for all ingredients (milk, eggs, etc) to be at room temperature.
What is the safe method of bringing these ingredients to room temperature? Do you just leave them out for a few hours?
Alternatively, what is a quick way to accomplish this? Heat them up? Place them in room temperature or warm water baths?
If it is something like the eggs for baking a cake then you take out the number of eggs you need for the recipe and let them sit on the counter for about an hour before you start putting your ingredients together. I've been baking for a great many years and even if the eggs are still a little chilly it won't do any harm to a cake or cookie recipe. It might make a difference for bread recipes but the warm water used to activate the yeast will usually bring up the temp of other ingredients to where you need it.
Eggs are actually pretty safe to leave at room temperature anyway; supermarkets don't bother refrigerating them, and you can be damn sure they're not going to risk losing any money through spoilage. I keep mine in a ceramic bowl on the counter top.
In general, simply take the required ingredient out of the fridge a couple of hours before use, keep it away from heat sources and out of direct sunlight.
Specifically in regards to leaving milk out, at one time I worked in an institutional kitchen. The milk we got had a table on it giving temperatures and the time it was safe to leave out in those temperatures. I don't remember the exact numbers, but the table went up to 90 degrees Fahrenheit. There should be no problem leaving milk, and most other ingredients, out for an hour or two at room temperature.
