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: Like many people, I rely on coffee in the morning to really get me going for the day. I always use more than the directions require to get more caffeine for that extra morning jolt.How much ground coffee should I use to reach caffeine critical mass in my brew? Is there a formula for volume of grounds per unit of water that I can use so I can get the maximum caffeine experience without wasting coffee?

A: How can I maximize the caffeine content of my coffee?
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Q: I want to make ice cream at home for diabetics without a machine. I'd want it to be sugar-free. What kind of base ingredients should I use? Will the any of the no machine methods here be better or worse, or require modification, since I'm not using sugar?

A:
How do I make sugar-free ice cream without a machine?
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