In the meantime, while potatoes are boiling, pour milk into small pot, add bay leaf, rosemary and herbs de provonce (optional). Smash garlic clove and add it, too, peel and all. Bring to boil and immediatly lower heat to a very low simmer.
Drain potatoes. If you use a ricer, rice them through now. Add butter, salt (and cheese, if you want); mix or mash it all together.
Take milk off heat. Remove the rosemary sprig and bay leaf. Slowly mix it into the mashed potatoes until your velvety masterpiece is complete! Taste it and add salt if you want. If serving on the table, garnish with a tiny sprinkle of herbs de provonce, or chives, or chopped parsley or dill...