beans!

[sage]

Dear cooks who know more than me,

I've been cooking with dry beans for the last some-odd months to save money and reduce exposure to harmful toxins and such. The cookbooks say:

1. soak beans 8 hrs or overnight.
2. parboil soaked (rinsed, drained) beans at a rolling boil for 10-12 minutes.
3. rinse and cover with fresh water and simmer for 45 minutes to an hour or more, depending on the kind of bean.

Got it. The thing is, after I parboil? I simmer for 25 minutes and the beans are done!

I'm generally cooking one cup of any of these varieties: black, pinto, lima, rattlesnake, kidney, or small red. Chickpeas and chana dal take longer -- much closer to what directions indicate.

Why are my beans done so fast? If I look away for like, a minute, they get mushy and/or burn to the bottom of the pot.

Also, I'm at practically sea level, whatever San Antonio is at, if that matters.

I am so confused. I mean, they taste okay, but I keep thinking I must be doing something wrong! Help?

Thank you!