Using a 9x13 pan, go ahead and make the white cake according to the directions on the box. After it's done, let it cool off for about 10-15 minutes.
Grab a wooden spoon by the bottom and using the handle, poke holes in the cake. Space them about an inch apart. Try to go about halfway down. That's the ideal depth.
Using a microwave-safe bowl, it's time to mix the white chocolate chips and sweetened condensed milk. Heat the mixture until it's smooth and combined nicely.
In a separate bowl, make the strawberry Jell-o. Make sure it's completely dissolved. Once it is, mix into the white chocolate-condensed milk mixture. Pour that over the top of the cake and make sure that it fills the holes you made earlier.
In a chilled bowl, whisk the heavy whipping cream, sugar, and vanilla extract. Beat the cream until it forms stiff peaks.
After the cake has completely cooled, spread the whipped cream evenly over the top of it.
However you wish to do it, arrange the sliced strawberries on top of the whipped cream layer.
To ensure the maximum flavor possible, it's best to put the cake in the fridge for 6-8 hours, the longer the better. The longer it chills, the more decadent it becomes!