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Many commercial cake mixes use vegetable oil, but I have seen some (usually 10% or less of what the store carries) that are "Butter Recipe".These use butter instead of vegetable oil. What is the difference in these? And is the reason you do not find many in stores is because it is not popular, or costs more, or something else?
What is the difference between regular (vege. oil) and butter recipe cake mixes?

Today I sauteed a quarter cup mushrooms in 3 tbsp butter and added 250ml cream. Everything was set for me to add the ricotta and finish the Alfredo, but it only partly melted. Beyond a certain point, there were some "cheese crumbs" that no amount of heat could dissolve, thus robbing me of a velvety textured Alfredo.I have successfully made Alfredo with ricotta cheese before. Is there any reason as to why the ricotta did not completely melt? The ricotta package was only opened a few days, so it couldn't have gone bad.
Why did my ricotta cheese did not completely melt in the Alfredo?

I am relatively new to deep-frying. Having seen the questions about oil reuse and conservation, I'm still at a loss about what's going on with my oil...My sunflower oil foams like crazy. I've been reusing this oil for a while now and was going to discard it, however a friend of mine told me this oil was still looking good. Relatively clean (I filter it regularly), no off smell and it doesn't smoke (in my fryer, that is). I only fry potatoes in this batch of oil to avoid flavor transfer. These are cut into French fries, chips or straw potatoes. Specially the chips and straws retain a lot of water, and I guess that has something to do with it.Also, I noticed the frying takes longer with the foaming oil.Edit: I've tried poaching(?) the French fries, but they foam during poaching. Then when frying, they really foam. I have to keep an eye on it or the oil spills over the top. Anything I can do about it, or should I just go ahead and discard the oil altogether?Edit: Serious Eats has an article about frying oil.

Frying - Oil foams