Here are some guidelines on how to cook Lentils/dal/dhal/grams/peas:

Dal or lentils is the staple food in every Indian home. Both the rich and the common person who lives on the street enjoy it. It is what chicken is to the west – it is India’s comfort food and also It’s usually the starter of every meal eaten with hot steaming rice or with freshly made chapati (leavened bread) straight off the girdle. Dal is everyman’s meal and one of the healthy dishes in an otherwise red hot-chilly pepper Indian diet. The desert cuisines of Indians use an immense variety of pulses and preserves to substitute for the relative lack of fresh vegetables.  It is also dried with spices to produce spice capsules to add to foods. The world of dal in India is truly one of India's culinary gem. 
Most dals do not need soaking.  They may be boiled with turmeric and ginger and then seasoned with sautéed onion and tomatoes.  Roasted or oil sizzled cumin seeds adds an extra dimension to dals and aids in digestion of dals.

Tempering Dal
The tempering, or seasoning, is what makes the dal come alive.  Turmeric gives dal the lovely golden hue. Dal is fat free and nature has designed it to absorb various combinations of seasonings and spices.  There are innumerable variations of the simple seasoning and one can create their own individual taste. The standard ingredients include mustard seeds, jeers, red chilies or chili powder, hing/asafetida, onions, green chilies, ginger, garlic, tomatoes, garam masala, curry leaves. The fat of choice is ghee in the dal.  Oil brings in a acidic after taste but if one is a vegan we suggest sunflower oil.  seasonings are enhances in the ghee medium pushing their curative properties higher.  Dals are commonly garnished with fresh chopped coriander and served hot.

Dal Common Vegetable Combinations
Dal + greens.
Dal  + pumpkins, squash
Dal + Carrots

Dal Common Preparation Methods
Dry dal. 
Sprouted dal
Dal Soups

________________________________________________________

For Pressure Cooking there is no need of soaking the lentils.  If you are going to cook lentils often it would be a good idea to invest in a pressure cooker

Let the dal cook and open the pressure cooker when the pressure subsides by itself.
________________________________________________________

Cooking in a pot with a cover - Once the dal comes to a boil, remember to cover it and set on a low flame. While cooking on the stove allows you to constantly check the dal's water level, it takes a lot more time.