Spray cake mold, and preheat oven to 350 degrees. Prepare cake batter according to package directions, and pour into mold. Bake about 35 minutes or until springs back and toothpick inserted in center comes out clean. Let cool completely.
Prepare pudding mix using 1 1/2 cups milk. Refrigerate.
When cake has cooled, carefully remove from mold to a tray. Use a cake leveler to flatten out the cake top. and then scoop out some of the cake insides to resemble a hard-boiled egg with yolk removed. Reserve cake crumbs.
Add cake crumbs to refrigerated pudding; mix together well. Spoon into hollowed out cake middle.