Heat the milk till it boils. Some people simmer it on low heat to thicken it further.
Now let the milk cool down so that your milk is lukewarm. My test is to insert a clean finger. You should be able to bear the temperature of the milk while it feeling warm.
Now froth the milk. I do this by transferring milk from one pan to another for 4-5 times till the milk is frothy. Then I add the culture to the milk and toss it once or twice more till assimilated.
Now, leave for the curd to set in a warm place for 5-8 hours depending upon how how or cold the climate is.
You will get thick curd to consume. Refrigerate as soon as the curd sets.
Notes
Use whole milk for a thicker set curd. As I mentioned, you could further simmer the milk for 10 minutes to make sure that it is thick when set. Make sure you don’t burn the milk.
Use good culture and bring it to room temperature before adding to the milk. You can use anywhere between 1 tsp. to 1 tbsp. culture for 1 litre or 34 oz. of milk.
Do not use sour curd culture or your curd will turn out sour.
Frothing the milk makes it set thick. Also setting it in an earthen vessel gives a nice thick set curd. You could use a metal container too.
If you live in a very cold place then you may take more hours to get set curd. Leave your milk vessel in a slightly wam place like an oven with the light on to expedite the process. You may also put it in a casserole for faster setting.
Some people add a broken dry red chilli in the milk while setting to make thick curd. I haven’t tried this trick and no it will not make your curd spicy.
The consistency of your curd will depend upon the kind of milk you use. I use packaged milk. Those using milk straight from the dairy may find a different consistency.
If you have never set curd before, try this method (maybe 2-3 times to get the hang of exact process) and you will have delicious thick curd at home.