Heat oven to 375°F. Remove pie crusts from pouches; place flat on work surface. With 2 1/2-inch round cutter, cut 12 rounds from each crust. Press each round in bottom and up sides of ungreased mini muffin cup.
In medium bowl with electric mixer, beat cream cheese and blue cheese on medium speed until smooth. On low speed, beat in half-and-half, salt and egg until well blended. Spoon 1 scant tablespoon mixture into each crust-lined muffin cup. Top each with 2 walnut pieces or 1 walnut half.
Bake 15 to 20 minutes or until filling is set and crust is light golden brown. Cool 5 minutes. Remove from muffin cups. Garnish with parsley. Serve warm.