[ 2008-04-15: For reference, tonight I made this with turmeric, coriander seed, ajwain, fenugreek, allspice, black pepper and (whole) black mustard seed at the start (and no onion, garlic or ginger); green lentils; cardamom seed, cumin, asafœtida, flaked dried chilli, dried green pepper flakes, a bit more black pepper, salt and cooked shredded chicken half way through; fresh coriander and lemon juice just before serving. With brown basmati and finely chopped and fried shallot and garlic to garnish, it was one of my better instances of the recipe. ]
I've a generic dhal I make with variants, depending on context, accompaniments and available ingredients. The pulses I use are usually green, brown or puy lentils, or mung beans: all take near as damnit the same time to cook so the method doesn't change.
First, find and (where appropriate) grind the initial set of spices: I usually use turmeric and coriander, plus fresh ginger. Depending on the context, I might put ajwain in, or fenugreek; depends on what would go with other components of the meal.
I usually chop an onion and, more often than not, whizz garlic with the ginger. Neither is compulsory if you're feeling all Vedic of a sudden.
Fry up whatever you've picked from the above for a bit in groundnut oil, or your preferred source of lipids, then add your pulses, stir in and add ~2.5-3 times the quantity of water: you're looking for enough to cook and soften the pulses in without drowning them altogether. Better a bit too little as you can always add more as cooking progresses.
Bring to the boil and simmer gently for 40-45 minutes. You'll likely be putting your rice on about 10-15 minutes into this.
Prepare your second stage spices. I use ground (or occasionally fresh) chilli, cumin (normal or Kashmiri) always; often cardamon seeds and asafœtedia - certainly the latter if I've omitted garlic earlier. Oh, and fresh ground pepper and salt too. Stir that little lot in.
Five or so minutes before you want to serve, add spinach a little at a time as it wilts in.
Finally, just as you're ready to serve, stir in the juice of some proportion of a lemon (I'd say ~one lemon per four servings).
That's it. You can vary this as you will: a common addition here is to add shredded cooked chicken around when the second tranche of spices get added. Use your imagination!