Preheat oven to 300°F (150°C) and line a baking sheet with parchment paper.

In a clean, dry bowl, beat the egg whites with cream of tartar until stiff peaks form.

In a separate bowl, beat the softened cream cheese until smooth. Then, beat in the egg yolks until well combined.

Gently fold about one-third of the whipped egg whites into the cream cheese mixture to lighten it. Then, carefully fold in the remaining egg whites until just combined, being careful not to deflate the mixture.

Spoon mounds of the mixture onto the prepared baking sheet, about 3 inches in diameter.

Bake for 20-25 minutes, or until golden brown and firm to the touch.

Let cool completely on the baking sheet before serving.