I won't lie to you. A cake this amazing takes some work (and time!). But when you break down the recipe step-by-step, it's far less intimidating than you might think.
First, make the Nilla Wafer crust. Crush the cookies, mix them with melted butter and press it all into a springform pan. Done.
Next, make the mousse. Start by pureeing blueberries then stir in lemon zest and lemon juice. Sprinkle a packet of gelatin on top and let it sit until softened, 5 to 10 minutes. While it's setting, make white chocolate ganache. (It's not as thick as ganache, but the process is pretty similar.) Pour hot heavy cream over white chocolate chips and stir until smooth. Let cool slightly, then fold in the blueberry gelatin mixture. Stick this in the fridge while you make whipped cream.
Yes, you might as well whip your own cream. In the grand scheme of things, it's a small extra step that makes a big difference. Once the whipped cream is nice and fluffy, add the white chocolate blueberry mixture and fold until it's a pretty shade of violet. Voila! You have lemon blueberry mousse! Pour mousse mixture over crust and refrigerate until set, about 4 hours.
Last but not least, make the sugared blueberries. When just washed (and not dried thoroughly), sugar will stick to the berries very nicely. (Though we add a touch of lemon juice to balance out the sweetness.
