Preheat oven to 375°. Line bottoms of 2 greased 8-in. round baking pans with parchment; grease paper.
In a large bowl, beat eggs on high speed 3 minutes. Gradually add sugar, beating until thick and lemon-colored. Beat in pumpkin. In another bowl, whisk flour, pie spice, baking powder and salt; fold into egg mixture. Transfer to prepared pans, spreading evenly.
Bake until a toothpick inserted in center comes out clean, 15-20 minutes. Cool in pans 10 minutes before removing to a wire rack; remove paper. Cool completely.
For filling, in a large bowl, beat cream until stiff peaks form. In another large bowl, beat cream cheese and confectioners' sugar until blended; fold in whipped cream. Spread between cake layers. Refrigerate at least 1 hour.
Place chocolate in a small bowl. In a small saucepan, bring cream just to a boil. Pour over chocolate; let stand 5 minutes. Stir with a whisk until smooth; cool slightly. Press plastic wrap onto surface of ganache; cool to room temperature. Spread over cake. Refrigerate until serving.