Place potato cubes in a large pot and cover with cold salted water. Bring to a boil over high heat, then reduce to medium-high and cook for 15-20 minutes until fork-tender.
While potatoes cook, warm the heavy cream and herb butter in the microwave for 30 seconds or in a small saucepan over low heat. This step is crucial for creamy potatoes.
Drain the potatoes well and return them to the hot pot. Let them sit for 1-2 minutes to evaporate excess moisture.
Rice the potatoes using a potato ricer for the creamiest texture. Alternatively, mash with a potato masher until smooth.
Add the warmed herb butter and fold gently until incorporated. Pour in the warm heavy cream gradually while folding to your desired consistency.
Season generously with salt and pepper. Taste and adjust seasonings as needed.
Transfer to a serving bowl and top with extra herb butter if desired. Serve immediately while hot.
Notes
Warm your liquids: This is the most important tip! Cold heavy cream and butter can make potatoes gummy. Always warm them before adding.Rice your potatoes: For the creamiest, fluffiest texture, use a potato ricer instead of a masher. It prevents overworking the starches.Extra creamy: Add more butter and heavy cream to taste.No herb butter? Use Kerrygold Garlic & Herb Butter as a quick alternative that packs in similar flavor.Storage - Refrigerator: Store leftovers in an airtight container for up to 4 days. Reheat gently on the stovetop with a splash of heavy cream.Storage - Freezer: Freeze in portions for up to 2 months. Thaw overnight in the fridge and reheat with extra butter and cream to restore creaminess.Reheating: Reheat on the stovetop over medium-low heat with a splash of heavy cream, stirring occasionally. Microwave individual portions for 1-2 minutes, stirring halfway through. Add extra butter if needed.