Peel and chop the russet potatoes.
Place the peeled, chopped potatoes into a large pot of salted water. Bring to a boil over medium-high heat and cook until the potatoes are fork-tender, about 15–20 minutes.Drain the potatoes and return them to the pot.
In a small saucepan, place the garlic, sage, rosemary, chives, thyme, butter and heavy cream. Bring to a light simmer over low heat. (Warming the cream helps it incorporate better into the potatoes without cooling them down.)
Using a potato masher or ricer, mash the potatoes while still hot until they are smooth and free of lumps.
Pour the warm butter and milk mixture through a sieve into the mashed potatoes.
Add the shredded cheddar cheese, stirring until it melts into the potatoes, creating a creamy, cheesy texture.
Season with salt and pepper to taste. Add more heavy cream if you want a creamier consistency.
Garnish with chopped chives and an extra pad of butter.