Preheat your oven to 350°F. Grease two 9-inch round cake pans (or similar size) and lightly coat the bottoms with sugar—this helps create a subtle crispy texture on the cake exterior. In a large mixing bowl, combine the vanilla cake mix, eggs, water, and melted butter. Mix on medium speed for about 2 minutes until the batter is smooth and fully combined. Divide the batter evenly between the prepared pans and smooth the tops. Bake for 28-32 minutes, until a toothpick inserted in the center comes out clean or with just a few moist crumbs. The cakes should be golden and spring back when lightly touched.
Remove the cakes from the oven and let them cool in the pans for about 10 minutes. Run a thin knife around the edges of each pan to loosen them, then invert onto wire cooling racks and let cool completely to room temperature—this takes about 45 minutes to an hour. Once cooled, use a serrated bread knife to carefully trim the domed tops of each cake to create level, flat surfaces. I like to do this by gently sawing in a circular motion while rotating the cake, which ensures an even cut and creates better stability for stacking.
In a medium bowl, combine the softened cream cheese, sugar, and vanilla extract. Beat on medium speed for 2-3 minutes until the mixture is smooth, creamy, and light in color. Scrape down the sides of the bowl occasionally to ensure everything is evenly combined. The cream cheese should be at room temperature for the best results—cold cream cheese will create lumps in your frosting.
Pour the heavy cream into a clean, cold bowl and beat on medium-high speed until stiff peaks form—this should take 3-4 minutes. Gently fold the whipped cream into the cream cheese mixture from Step 3 using a spatula, being careful not to deflate the whipped cream. Mix just until combined and no streaks of white remain. The frosting should be light, fluffy, and spreadable. If you're using a piping bag, transfer the frosting to the bag fitted with a large round tip, or simply reserve it in a bowl for spreading with an offset spatula.
While the cakes cool, hull the fresh strawberries and slice them into quarter-inch pieces. Place the sliced strawberries in a bowl and gently toss them together. If you prefer a slightly sweeter berry filling, you can sprinkle 1-2 tablespoons of sugar over them and let them sit for a few minutes to release their juices. I find this creates a more cohesive filling that won't slide around when you stack the cake.
Place the first leveled cake layer on your serving plate or cake stand. Spread or pipe about half of the frosting from Step 4 onto the top of the first cake layer. Arrange about half of the sliced strawberries from Step 5 over the frosting. Carefully place the second cake layer on top and press gently to secure. Pipe or spread the remaining frosting over the top and sides of the assembled cake, then arrange the remaining strawberries decoratively on top and around the sides. Chill for at least 30 minutes before serving so the frosting sets and the flavors meld together.