There is nothing "authentic" about my reductionist method of Indian cooking except for the taste -- the old-fashioned way was to stir and stir. Bibiji, my grandmother, used to make and freeze the masala for quick curries - she was an early adopter of all kitchen technology. In the cities in India, the blender method of making Masala is popular, but the crockpot has not yet found a following. I find that using a crockpot helps when you're writing and tend to forget things left cooking on the stove...prevents me from burning the house down.
Enjoy!
Shauna Singh Baldwin

Five steps to any curry:
1. Make Easy Any Curry Masala (sauce).
2. Add Masala and Vegs/Meat/Poultry to Crockpot
3. Add Tarka (infused oil)
4. Add a 1/4 cup coconut milk for Thai curry/2 tbsps cream or yoghurt for Punjabi-style curry
5. Add garnish of dhania (cilantro)

Easy Any Curry Masala (sauce):
4 tomatoes - red as possible, firm but not soft
1 pkg frozen chopped onions - Orieda is a good brand, but any will do.
Blend in blender till pureed.
Divide into two portions - freeze one and use one.

To use Masala (Sauce) in Curries
For instance -- thaw in microwave and place in the bottom of the crockpot:
   4 chopped potatoes, (1.2 lbs)
   1 can Garbonzo beans
   1/4 pkg frozen petite peas (thaw by  microwaving for 3 mins)
Add Easy Any Curry Masala.

OR:
For instance, thaw in microwave and place in the bottom of the crockpot:
1 pkg chopped mushrooms
1 pkg frozen asparagus spears
Add Easy Any Curry Masala.
and you get Mushroom-Asparagus Curry

Now add the finishing touch - tarka.
To make tarka (infused oil):
In a small frying pan, heat one tablespoon of vegetable ghee on medium (don't substitute butter or margarine or olive oil or you will completely lose the South-Asian taste and don't buy butter ghee unless you want to get fat). When hot but not smoking, add one tablespoon of garam masala, one teaspoon of turmeric, one teaspoon ginger paste, or ginger-garlic paste if you like garlic. Mix with a spoon and heat for 3 mins.
Add this tarka to the curry in the crockpot.
Creativity consists in going beyond this basic recipe to experiment with many spices. Also, vary the spices so that all your dishes don't taste the same. I usually add one bay leaf to be removed before serving, and a stick of cinnamon to the above but no harm done if you leave these out.
Turn on the crockpot on low.
Leave on for 4 hours min. If more, don't worry, it can't burn.
The longer you leave it, the more mushy the curry, but it will still taste fine.
When you're ready to eat it,
Add 1 tsp salt or more, pepper to taste, fresh coriander as garnish.
And enjoy!
Note: I don't add salt while cooking - it dehydrates.

Enhancements and alternatives:
In the above recipe, get creative and add a pkg of thawed frozen vegs of your choice. If you're making non-veg, add chicken and you have Chicken Curry.
Substitute a pkg (1.3 lbs or so) of stew beef and a peeled potato and you have a great Meat curry. Substitute a pkg (1.3 lbs or so) of ground lamb/beef/turkey and you'll have a nice Keema curry. Mutton is most authentic.
Add 1/4 cup whipping cream to the Chicken Curry recipe and you have a good approximation of butter chicken (and will get fat).
Mixes of Meat and Vegs become Pakistani/Mughal style curries. For instance, ground lamb/chopped spinach, stew beef/chopped collard spinach..
Addition of very hot spices make curries South-Indian in style.
You can also buy packages of Chicken curry masala, Veg Curry Masala at the Indian Grocery Store. DO NOT buy the spice called "curry" in North American grocery stores -- it is some vile mixture and there is no such thing in India.

Beginning Shopping List from an Indian Grocery Store:
1 box Garam Masala
1 box Turmeric
Ginger-Garlic paste or Ginger paste
Frozen Naans and Rotis (2 pkgs of 4) Avoid Frozen Parathas - very fattening.
Pickles
Fresh Coriander leaves (1 bunch).
At the Indian Grocery Store, avoid Patak's canned curry masalas - take a look at the number of grams of fat!
However, their pickles are very good - Mango, Mixed, Lime, and Tomato pickle.

Beginning Shopping list from a North-American Grocery Store:
2 pkgs of frozen onions
1 pkg of frozen mixed vegs of your choice
Pkg of petite sweet peas
2 large baking potatoes
8 firm red tomatoes for curry (two batches of above curry masala recipe)
Fat-free plain yoghurt - Dannon is a good brand.
Whole wheat or Flour tortillas (if you were unable to get frozen Naan or roti at your Indian grocery store). Get a package of 8-10 and make sure it's resealable. Heat in microwave 10 secs/tortilla, or wrap in foil and heat in the conventional oven 15 mins at 250.
(Btw, Tortillas are great with a slice of Brie and a tsp of tomato pickle as a snack. Wrap and zap for 10 secs in the microwave.)