I found this in a Hershey Cookbook called Hershey Classic Cookbook. It has some of the elements you requested but says nothing about an ice cube tray...I was wondering if maybe this was your moms own addition...possibly she made the topping and froze it by mistake or froze fresh strawberries to use in the recipe. You know how our memories play tricks on us as the years pass.

Strawberry Chocolate Pie

Cocoa Crumb Crust (recipe follows)
3/4 cup Hershey's Syrup
1/2 cup sweetened condensed milk
1 egg yolk, beaten
1 teaspoon vanilla
1 cup heavy cream
1 egg white
1 tablespoon sugar
Strawberry Topping (recipe follows)

Prepare Cocoa Crumb Crust; Set aside.
Combine syrup, sweetened condensed milk and eg yolk in small heavy saucepan. Cook over medium heat, stirring constantly, until mixture boils. Remove from heat; stir in vanilla. Cool; chill thoroughly. Whip cream until stiff; fold into chocolate mixture. Beat egg white in small mixer bowl until foamy; add sugar and beat until stiff peaks form. Fold into chocolate mixture. Pour into prepared crust. Cover; freeze until firm.

Prepare Strawberry Topping; spoon onto frozen chocolate filling. Cover and freeze until serving time. Garnish as desired

8 servings

Cocoa Crumb Crust
1 1/2 cups vanilla wafers crumbs (about 45 wafers)
1/3 cup Hershey's Cocoa
1/3 cup confectioners' sugar
6 tablespoons butter or margarine, melted

Combine crumbs, cocoa and confectioners'sugar in medium bowl; gradually add melted butter, stirring to completely coat crumb mixture. Press firmly onto bottom and up sides of 9-inch pie pan; freeze.

Strawberry Topping

1 package (10 ounces) frozen sliced strawberries, thawed
1 cup heavy cream
2 tablespoons sugar
2 tablespoons light corn syrup

Drain strawberries; mash or puree in blender or food processors to equal 1/2 to 2/3 cup. Whip cream and sugar until stiff; fold in strawberry puree and corn syrup.