Usually when an Indian recipe calls for golden brown or caramelized onions,
the onions are browned in a fairly large amount of oil. Here is a method
requiring very little oil using a non-stick pan.

Slice the onions into very thin, even slices or chop the onions into small
uniform pieces. heat about 1 tablespoon of oil over moderate heat. The
amount of oil depends upon the amount of onions to be cooked. Stir the
onions for 2 minutes. Reduce the heat to low. Add about 2 tablespoons of
water and continue cooking, stirring constantly. If cooking large
quantities, add additional water 1 tablespoon at a time if the onions begin
sticking to the pan or fry too rapidly. This allows the natural moisture of
the onions to be coaxed out while browning. Continue frying until the
onions are golden brown. This process can take about 20 minutes. When
simmered slowly, the onions add a rich dimension and melt into the sauce,
thickening it as well. Brown fried onions can be prepared in large
quantities and refrigerated or frozen and defrosted when needed. Once
defrosted, they cannot be refrozen so it is best to package them in small
quantities.

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