Peel and slice the potatoes
Transfer the potato chunks to the sauce pan. Add water to cover (1 inch above)
Put the sauce pan on the stove top, and heat to boil
Turn heat to medium, and simmer for 15-25 mins (depending on the chunk size), to the point where when you stab a chunk with a knife, it drops freely from the knife
Remove the sauce pan, drain the water, and smash/mix the potatoes with the spoon
Once the potatoes are smashed and cool down a little bit, transfer it to the strainer
Use the spoon to press the potato to help it run through the strainer
Once all the potato is pushed through the strainer, scrape the other side of the strainer to collect all the mashed potato
Transfer the filtered mashed potato back to sauce pan, and place the pan on very low heat to keep the pan warm
Weight the butter, add to the pan, and mix vigorously with the spoon
Adjust the flavor with an addition of salt
Warm the milk up in the microwave. Pour the milk in 3-4 portions to the sauce pan and mix.
Transfer the smashed potato to the strainer (preferably a finer one) by scraping and pressing the potato against the strainer
Once all the potato runs through the strainer, wipe the bowl edge. Use the back side of the spoon to make some groves on the smashed potato surface. Sprinkle some finely sliced parsley or herbs to decorate