after u chop potatos.. put them in boiling water n add SALT.. (take 10mins cooked, 15-20mins soft)
If u planning to make mashed (potato) cook about 15mins..(throw 3/4 of the pot water) turn middle heat n pepper, milk, better.. cook 5mins .. for sure smooth n soft.
also you can buy salad potato. Thats small n fast cooked