Cut the Yukon gold potatoes into even-sized chunks (about 2-3 inches) to ensure they cook uniformly. Place them in a large pot and cover completely with cold water. Bring to a boil over high heat, then reduce to a simmer and cook for 15-20 minutes until a fork easily pierces the largest piece. The potatoes are done when they're completely tender but not falling apart. While they cook, reserve the pot you'll use for mashing so it's ready to go.

Carefully drain the cooked potatoes in a colander, reserving about 1 cup of the starchy cooking liquid—this is your secret ingredient for creamy mashed potatoes without milk. Return the drained potatoes to the original pot (or a large bowl if you prefer). I like to use the reserved potato water because it contains natural starches that create a silky texture better than any milk could.

Add the butter, kosher salt, garlic powder, and cracked black pepper to the hot potatoes. Using a potato masher, begin breaking down the potatoes with firm, controlled strokes—work methodically until most lumps are gone. Gradually add the reserved potato cooking liquid a little at a time, mashing between additions, until you reach your desired consistency. Start with a smooth texture and add more liquid if you prefer them creamier. I find that stopping when there are still a few small lumps gives the best texture—completely smooth potatoes can become gluey if overworked.

Transfer the mashed potatoes to a serving dish. If using fresh herbs, finely chop the thyme, parsley, or chives and scatter them over the top just before serving for a pop of color and freshness. Serve immediately while still hot for the best creamy texture.