In a bowl of a stand mixer fitted with the paddle attachment, combine the cream cheese, sour cream, and lemon juice, increasing the speed as the ingredients combine, until fluffy, lightened, and spreadable, just 1 to 2 minutes. Alternatively, use a medium mixing bowl anda. stiff spoon to combine and then stir and whip vigorously to aerate and lighten the mixture.
Pack the schmear into a ramekin or two, cover, and chill until ready to serve. It will keep for 1 week in the refrigerator.