Mix your graham cracker crumbs with melted butter until it resembles wet sand. Press the mixture firmly into the bottom of an 8-by-8-inch dish, using the bottom of a measuring cup to pack it down really tight. This gives you a solid base that won't crumble when you add the layers. Let it sit while you prep the whipped cream mixture.

Pour heavy whipping cream into a large bowl and whip with an electric mixer on medium-high speed for about 2 minutes. When it starts getting fluffy, add powdered sugar and vanilla extract, then whip for another 1-2 minutes until stiff peaks form. Don't walk away — I learned this the hard way when mine turned into butter (whoops).

Toss your sliced strawberries with the lemon juice and let them sit for two minutes. This helps them stay bright red instead of turning brown during storage. Gently fold half the whipped cream into the white chocolate chips, creating a mousse-like layer.

Spread the white chocolate whipped cream mixture over your graham cracker crust in an even layer. Use an offset spatula if you have one, but honestly a regular spatula works fine — it doesn't need to be perfect. The berries are gonna cover any bumps anyway.

Arrange half the strawberry slices in a single layer on top of the cream mixture, then scatter half the blueberries over them. Take your time with this part since it's what everyone sees — this is your chance to make it look incredible. You're basically creating your patriotic stripes here.

Top the berries with the remaining whipped cream, spreading it smooth and even. Then add the rest of your berries on top in whatever pattern makes you happy — rows, clusters, whatever you like. This is where the patriotic icebox cake really shows off visually.

Sprinkle crushed pistachios across the top for a finishing touch and pop the whole thing in the fridge for at least 4 hours (overnight is even better). This chilling time lets the crust firm up and everything meld together. When you pull it out right before serving, it'll slice cleanly instead of falling apart.