Beans...

Get some pintos (I like cooking two pounds at once) and a heavy-bottomed, large pot.

Sort & wash the beans, then place in the pot, covering them with water, then filling until there's about an inch and a half to two inches of water above the beans (it's pretty subjective). Bring to a boil, then reduce heat to 1/4 or so. You're looking for that happy medium between low and medium, one we might call medium-low, where the beans are still simmering, but large bubbles aren't forming at all. Barely.

Add during cooking:

1 tsp salt
1/2 tsp pepper
bit of cumin
shake of cayenne pepper
4-6 of those dried chiles japones you find in the dried mexican food & spices section. (I'm pretty sure these are just serranos)

1/4 to 1/2 onion, chopped
1 tomato, chopped or one can hunt's diced tomatoes

cook for more than two hours, partially covered, adding about a cup of water when the beans break the surface of the water. When it seems that they are beginning to get done, try smashing them against the side of the pot with a spoon. If they look chalky, they are not tasty yet. Once they look like they are done, they may very well be. This is the point when I put them on the lowest possible heat and cook 'em for about an hour longer.