Peel the 3 lb Yukon Gold potatoes peeled and cut into 1½-inch chunks and cut them into uniform 1½-inch chunks. This ensures they cook evenly. Place them in a pot (Large) and cover with ¼ cup whole milk 1 tbsp kosher salt for the boiling water by at least 1 inch.

Add 1 tbsp of kosher salt for the boiling water to the pot. Bring to a boil over high heat, then reduce to a steady 3 lb Yukon Gold potatoes peeled and cut into 1½-inch chunks boil. Cook until the potatoes are completely tender and a fork slides through them with no resistance, about 15–18 minutes.

While the 3 lb Yukon Gold potatoes peeled and cut into 1½-inch chunks cook, warm the ¾ cup heavy cream and ¼ cup whole milk together in a saucepan (Small) over low heat, or microwave them in a measuring cups for about 60 seconds. Keep warm — cold dairy will cool down your mash and make it gluey.

Drain the 3 lb Yukon Gold potatoes peeled and cut into 1½-inch chunks thoroughly in a colander and return them to the hot pot. Shake the pot over low heat for 1–2 minutes to evaporate any remaining moisture. This step is key for fluffy, not watery, mashed potatoes.

Pass the potatoes through a 3 lb Yukon Gold potatoes peeled and cut into 1½-inch chunks ricer or food mill directly back into the pot for the smoothest result. Alternatively, mash with a hand masher for a more rustic texture. Do not use a blender or stand mixer — over-mixing releases starch and makes the potatoes gluey.

Add the 6 tbsp unsalted butter cut into pieces pieces to the hot 3 lb Yukon Gold potatoes peeled and cut into 1½-inch chunks and fold gently until fully melted and incorporated.

Pour in the warm ¾ cup heavy cream and milk gradually, folding gently after each addition until you reach your desired consistency. Add a splash more ¼ cup whole milk if you prefer a looser mash.

Season generously with 1 tbsp kosher salt for the boiling water and ½ tsp white pepper. Taste and adjust — 3 lb Yukon Gold potatoes peeled and cut into 1½-inch chunks need more salt than you think. Transfer to a ¼ cup whole milk serving mixing bowl, top with an extra pat of unsalted butter cut into pieces and 2 tbsp fresh chives thinly sliced if desired, and serve immediately.