To turn a high-calorie dish into a low-calorie one just requires you to think differently. Usually dalis boiled and then tempered (vaghar, tadka, etc) with fried spices. Instead of doing this, add your onions, tomatoes, ginger, garlic (whatever you generally use) to the dal when you are about to boil it. Then the tempering can be made with very little oil, whether it is jeera, rai or even just red chilli powder.
All kinds of koftas, which are fried, can be baked instead. Either you can bake the item in a pan and, when done, cut it into squares and put the curry on top or you can make roundels of the mixture, put them on a baking sheet or tray and bake.
The microwave oven also makes for easier fatless cooking in many cases. Some dishes are more conveniently cooked in a microwave. In addition, of course you can make dishes in larger quantity and freeze them for later use (if you have a deep freezer). These can then be thawed and reheated in the microwave oven.
For example, a traditional chocolate cake is very high in calories, but if we replace the sugar with sugar substitute and the icing with low calorie whipped cream, we can lower the amount of calories in the cake dramatically.
Sugar substitutes are usually the most common way of making a recipe low calorie. No real studies had been done on the benefits of sugar substitutes until 1994 when The Sweeteners Directive of the European Union was adopted and sugar substitutes began to be regulated and studies were introduced on the major benefits they posed to a low calorie diet.
Sugar substitutes are usually genetically altered sugars, or artificial sugars made in the lab. There are also natural sugars that have been found to have less calories than traditional cane sugar. One such sweetener is organic agave nectar, which is a natural sweetener extracted from the blue agave plant, or piƱa
There are several other ways to reduce calories in food in addition to sugar substitutes.
To replace high calorie fats, sauces and creams to add flavor to foods, many substitutes can be used. For example, herbs and spices, which are, for the most part, calorie free can be added to dishes such as mashed potatoes, meats and fish.