One of the take-aways from cooking split pigeon peas is that they remain firm up to the perfect cooking time, and can quickly turn mushy when going beyond that. If you do not mind a bit of mushiness and like them soft, this will be no problem. If however you like pigeon peas firm and not mushy, it is best to very slightly undercook them. They should still be done. Verify that the firmness works for you before straining by tasting a few of them with a small spoon.
Cooking split pigeon peas
Bring the water to boil in a large pan.
Rinse the peas in cold water in a strainer.
Add the peas to the boiling water and cook for about 20 minutes. Around the 18th minute, start tasting the peas to check if they are cooked. Re-check every 2 minutes.
Strain the peas, then rinse them in cold water to stop the cooking process, and remove any foam or mushiness that developed during the cooking. This will leave cooked but firm peas with a clean shape.