Pour your sweetened condensed milk into a big bowl, then add the heavy whipping cream. Whip everything together on medium-high speed for about 3-4 minutes until you get stiff peaks forming. Don't panic if it looks thin at first—it'll thicken up fast once the mixer does its job.

Sprinkle in the powdered sugar and vanilla powder while the mixer keeps going for another 30 seconds. This step stabilizes your whipped cream so it won't weep out liquid halfway through chilling. I learned this the hard way after my first patriotic icebox cake crowd got all watery by dinner time.

Grab a 9x13 inch baking dish and spread a thin layer of graham cracker crumbs on the bottom—just enough to cover it. This creates your base and keeps the whole thing from sliding around when people serve themselves slices.

Spoon about one-third of your whipped cream mixture over those crumbs and smooth it out evenly. Layer in half your sliced strawberries next, then press them gently into the cream so they stick. This patriotic icebox cake crowd really shines when those berries are visible in every cross-section.

Add another layer of graham cracker crumbs, then another third of whipped cream. Scatter your blueberries across this layer, making sure they're spread throughout for that patriotic color effect.

Top everything with your final layer of crumbs, then the last of your whipped cream smoothed flat on top. Now sprinkle those raspberries, toasted coconut, and pistachios across the very top for that fancy finishing touch.

Cover it loosely with plastic wrap and refrigerate for at least 4 hours—overnight is actually better because the flavors meld and the texture becomes more cake-like. When you cut into it the next day, you'll see those beautiful striped layers that make everyone go "wow."