A bowl of mashed potatoes with chives and butter
For The Creamiest Results, Add Eggs To Your Mashed Potatoes
By Chase Shustack
Some home cooks add heavy cream or cornstarch to their mashed potatoes, but others may find that using an egg can yield much creamier results without affecting flavor.
Eggs act as a natural emulsifier, giving the dish "body" (moisture, thickness, texture, and structure), and this principle still applies when using them in mashed potatoes.
To do so, prepare your potatoes as usual and add a mixture of one egg yolk and two tablespoons of heavy cream, milk, or half-and-half before mashing them.
The yolk will give your potatoes a bright gold or yellow color. Be sure to stir and mash them quickly, as letting them sit will cause the egg yolk to cook on its own.