Using a serrated knife, carefully cut the pound cake horizontally into 4 layers. Place the bottom cake layer cut side up on a plate. Spread 1/4 cup of the frosting over the layer. Sprinkle with 2 tbs. of the chopped candy. Spread the underside of the second cake layer with 1 tbs. of the frosting and place it, frosted side down, atop the candy-covered layer. Repeat with the third layer of pound cake.
Now spread the underside of the fourth layer with 1 tbs. frosting and place, frosted side down, atop the cake. Spread the remaining frosting over the top and sides of the cake. Sprinkle the top edges of the cake with the remaining 2 tbs. of toffee. Let stand until the frosting sets slightly, about 1 hour.
Serve immediately, or cover with a cake dome and store at room temp. For up to 1 day.