Step 1: Prepare and Bake the Cake
Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking pan with cooking spray or butter, then lightly flour it. In a large mixing bowl, combine the cake mix, eggs, water, oil, and vanilla extract. Beat with an electric mixer on low speed for 30 seconds, then increase to medium speed and beat for 2 minutes until smooth and well combined. Pour the batter into your prepared pan and spread evenly. Bake for 28-32 minutes, or until a toothpick inserted in the center comes out clean and the top springs back when lightly touched. The cake should be golden and pulling slightly away from the edges.

Step 2: Poke the Holes
Remove the cake from the oven and let it cool for about 10-15 minutes—you want it still warm but not piping hot. Using the round end of a wooden spoon handle, a fork, or a skewer, poke holes all over the cake, spacing them about ½ inch to 1 inch apart. Make sure to poke all the way down to the bottom of the pan for maximum filling absorption. Don’t be shy—you want lots of holes! This is the fun part and you really can’t mess it up.

Step 3: Prepare and Pour the Gelatin
While the cake is cooling slightly, prepare your gelatin mixture. In a medium bowl or large measuring cup, dissolve the strawberry gelatin powder in 1 cup of boiling water, stirring for about 2 minutes until completely dissolved. Add ½ cup cold water and stir well. Slowly and evenly pour the liquid gelatin mixture over the entire surface of the warm cake, making sure it seeps into all those holes you created. You’ll see the gelatin disappear into the cake—that’s exactly what you want! Use a spoon to help guide the gelatin into any holes that aren’t filling.

Step 4: Refrigerate
Cover the cake loosely with plastic wrap or aluminum foil and refrigerate for at least 4 hours, but preferably overnight. This chilling time is crucial—it allows the gelatin to set completely and the flavors to meld together beautifully. The cake will become incredibly moist and flavorful as it sits.

Step 5: Add Topping and Serve
Once the cake is completely chilled and the gelatin has set, remove it from the refrigerator. Spread the thawed whipped topping evenly over the entire surface of the cake using a rubber spatula or offset spatula. Arrange the sliced fresh strawberries on top in whatever pattern you like—you can cover the whole cake or create decorative rows. Add extra berries just before serving for the prettiest presentation. Cut into squares and serve cold. Keep any leftovers covered in the refrigerator.