Combine crumbs, walnuts, and butter, stirring well. Firmly press crumb mixture evenly in bottom and up the sides of a 9-inch pie plate or tart pan. Bake at 350 degrees for 5 minutes. Let cool.
Beat cream cheese at medium speed of an electric Stir in nectar and vanilla. Spread mixture evenly over prepared crust. Cut pears lengthwise into thin slices. Arrange pear slices on cream cheese mixture. Cover and chill at least 8 hours.
Combine 1/4 cup brown sugar and ginger in a small saucepan; cook over medium heat, stirring constantly until sugar melts. Drizzle mixture over tart. Serve immediately.