Place the cubed Yukon Gold potatoes into a large, heavy-bottomed pot. Fill the pot with cold water until the potatoes are completely submerged, then add a generous pinch of sea salt. Bring the water to a boil over medium-high heat.
Once the water reaches a rolling boil, reduce the heat to medium and maintain a gentle simmer. Continue cooking for approximately 15-20 minutes, or until the potatoes are easily pierced with a fork and tender throughout.
While the potatoes are cooking, melt the unsalted butter in a small saucepan over medium heat. Add the minced garlic to the melted butter and sauté gently for 2-3 minutes, or until the garlic is aromatic but not browned—this will infuse the butter with a delightful garlic flavor. Remove the saucepan from heat and set aside.
After the potatoes are cooked, carefully drain them in a colander and then return them to the same pot. Allow the potatoes to steam for a minute to evaporate excess moisture.
Use a potato masher or a sturdy fork to mash the potatoes until they reach a smooth and creamy consistency.
Gradually pour in the warmed heavy cream and the softened cream cheese, along with the sautéed garlic butter. Mix vigorously until all ingredients are fully combined and the mixture is luxuriously creamy.
Fold in the shredded sharp cheddar cheese and stir until melted and evenly distributed throughout the potatoes. Taste the mixture and season with sea salt and freshly cracked black pepper as desired.
Transfer the deliciously cheesy garlic mashed potatoes to a warm serving bowl. Garnish generously with finely chopped chives for a pop of color and an herbal touch.