Peel and clean your potatoes. Cut them into ~1 inch chunks, as close in size as possible.
Bring a large pot of water to a boil and add the potato chunks. Boil until the potatoes are cooked through, about 20-30 minutes. To check for doneness, stab a large potato chunk with a sharp knife, if the potato easily falls back off the knife, then they are done.
Drain the potatoes, then add them back into the pot. Add the butter, salt, pepper, and most of the half-and-half and truffle sauce (reserving a little to adjust as needed).
Mash and mix until you have a smooth and creamy consistency. Add more of the half-and-half as needed, to adjust the texture. Taste the mixture and add more salt, pepper, or truffle sauce to suit your taste.
Notes
Truffle sauce is made of truffle and olive oil. I use truffle sauce made with black truffles. Please note, the taste and strength of truffle sauce varies by brand, so please taste as you go and make adjustments. See the post section for more information.