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

Q: I've been making freezer burritos and eating them for lunches this week. The first batch I made microwave beautifully: just 45 seconds and they're hot all the way through. They were layered with rice, beans, and corn, nothing else (I don't eat cheese and I wanted them to be non-spicy so I can eat them when I'm feeling unwell). The second batch replace the corn with ground beef, cooked and seasoned. The exact same beans, the same rice made the same way. They're smaller, due to using a different package of tortillas; after almost 2 minutes of heating in the same microwave, the meat burrito I had brought still had cold spots in the middle. What causes this? Can I avoid it somehow? Should I mix the ingredients instead of layering?

A: Why do my meat burritos not heat well?
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Q: 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.

A: Frying - Oil foams
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Q: Broadly speaking UK recipes will specify amounts by weight (lbs/ounces or metric), whereas American recipes will specify amounts by volume (cups).Is there an explanation for how the two different approaches arose in the first place? I'm not talking about whether or not metric is used, but specifically about volume versus weight.

A:
Cups v. weighing scales - is there an historical explanation?
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