Bake the cake according to the directions on the package in a greased 9 X 13” baking pan.
Cool on a rack. Remove the cake from the pan and wash and dry the pan. Return the cake to the clean pan. Poke holes all over with a skewer.
Meanwhile dissolve the Jell-o in the 2 cups of boiling water. Drizzle over the cake, allowing the Jell-o to run into the holes. Chill overnight.
Fold together the Cool-Whip with the thawed strawberries (juice included) and frost the cake with the mixture. Chill until ready to serve. Should be well chilled when served.