There's nothing like creamy mashed potatoes. When you make mashed potatoes, never ever use a hand mixer or food processor. You will get glue. Instead, use a potato masher, ricer, or food mill. I like my mashed potatoes lumpy, but if you don't just keep mashing until you reach the consistency you like.
4 pounds Yukon gold potatoes, peeled and cut into 1-inch pieces
1 8oz container of sour cream
4 tablespoons (1/2 stick) butter
2 tablespoons chopped fresh parsley, plus more for garnish
2 tablespoons chopped fresh chives, plus more for garnish
Place potatoes in a large pot; cover with cold water by 1 inch, and add 1 teaspoon salt. Bring to a boil; reduce heat to medium-low, and simmer until potatoes are tender, 15 to 18 minutes. Drain; return potatoes to pot.
Stir potatoes over medium heat until dry (a film of starch will form on bottom of pot), about 1 minute. Remove from heat.
Add butter to mash potatoes and mash just until smooth. Add sour cream and stir until combined. Stir in parsley and chives; season with salt. Garnish with more herbs.