Prepare the frosting; in a large bowl, with the mixer at medium speed, beat cream cheese, lemon juice, and sugar until smooth.
Add cream and vanilla, increase speed to high, and beat until stiff peaks form.
Refrigerate the frosting while assembling the cake.
Cut the pound cake horizontally into 3 even slices. Place the bottom slice on platter; spread with half of lemon curd. Reserve ½ cup raspberries for garnish.
Arrange half of the remaining raspberries over lemon curd. Spread 1 side of each remaining pound-cake slice with jam.
Place 1 pound-cake slice, jam side down, over raspberry-topped cake. Repeat with the remaining lemon curd, raspberries, and pound cake.
Spread frosting over top and sides of cake. Cover cake loosely with plastic wrap. Refrigerate 2 hours, or overnight.
To serve, garnish cake with lemon peel and reserved raspberries. Use serrated knife to cut cake crosswise into slices. Drizzle with the chocolate syrup, if desired.