Step 1

Have an 8-inch x 8-inch pan ready. Place the bowl and beater from a mixer into the freezer, to use later for whipping cream.

Step 2

Slice the pound cake into ¼-inch slices. Trim off the dark crust to give the pieces straight edges.

Step 3

Arrange & fit slices into the pan: lay pieces of cake across the bottom of the pan to completely cover it, trimming pieces as needed to fill smaller spaces. Cut and fit pieces of cake around the inside walls of the pan and flush with the top edge. The inside of the pan should now be completely lined with cake.

Step 4

Place a few slices of pound cake into a food processor and pulse until the cake becomes fine crumbs. Repeat this until you have 1 cup of crumbs (about 3 ounces of cake.) Set aside.

Step 5

Prep the Key lime pie filling according to the package directions (using the egg yolks unless otherwise specified on your pie filling box.) Prepare the filling through the mixing and cooking steps, and then allow it to cool for about 10 minutes. Then pour it inside cake-lined pan. Spread the filling to an even layer. Loosely cover w/plastic wrap, refrigerate for hour.

Step 6

When the cake with Key lime filling has chilled the hour, spread the pound cake crumbs over the top of the lime pie filling layer.

Step 7

In a medium bowl, whisk together the white chocolate pudding mix and cold milk. Whisk it for 2 minutes.

Step 8

Set aside ½ cup of the pudding.

Step 9

Pour the rest of the pudding into the cake pan over the layer of pound cake crumbs. Loosely cover the top of the pan with plastic, and refrigerate it while prepping whipped cream. (if using canned or frozen whipped cream, skip to step 11.)

Step 10

With the chilled bowl and beater whip the cream: assemble the bowl and beater. Turn the mixer on low and slowly pour in the whipping cream. Increase the speed to medium-low or medium. The cream will whip faster the higher you can have your speed: find the highest speed you can go to without cream flying all over the kitchen!

Step 11

Beat the mixture until it has thickened and holds loose peaks. Depending on the speed you use, expect this to take less than 10 minutes. (Warm weather may also make the whipping process take a little longer.)

Step 12

Fold the reserved ½ cup of white chocolate pudding into the whipped cream. Spread this mixture evenly over top of cake, covering the pound cake edges.

Step 13

In a food processor, whiz the white chocolate chips until they are finely chopped. Spread the chopped chocolate over the surface of the cake. Sprinkle the lime zest over the chocolate. Wrap the cake with plastic wrap and refrigerate for 8-10 hours or ideally overnight.

Step 14

Slice the cake while cold and serve.