01 -
In a small saucepan, toss together your blackberries, granulated sugar, and lemon juice. Set over medium heat and cook for about 5-7 minutes, giving it an occasional stir. You'll know it's ready when the berries have softened and released their beautiful purple juice.
02 -
Place a fine-mesh strainer over a bowl and pour in the cooked berry mixture. Use the back of a spoon to press and squish everything through, leaving just the seeds behind. You want to extract every bit of that gorgeous purple puree! Set this aside to cool down to room temperature.
03 -
In a large mixing bowl, pour in your cold heavy cream. Add the powdered sugar and vanilla extract, then grab your mixer and whip everything until stiff peaks form - that's when you lift the beaters and the cream stands up with just a slight curl at the tip. Be careful not to overwhip!
04 -
Now for the magic part - gently fold your cooled blackberry puree into the whipped cream mixture. Use a rubber spatula and a light hand with a figure-eight motion, turning the bowl as you go. Keep folding until everything is evenly combined into a pretty lavender-colored mousse with no streaks remaining.
05 -
Spoon or pipe the mousse into individual dessert cups, glasses, or bowls. If you're feeling fancy, use a piping bag with a star tip for an elegant swirl. Smooth the tops if you've spooned it in.
06 -
Cover your mousse cups and pop them in the refrigerator for at least 2 hours, though overnight is even better. This chilling time allows the mousse to set properly and lets the flavors meld together beautifully.
07 -
Just before serving, top each mousse with a few fresh blackberries, a small dollop of whipped cream, and a mint leaf or two for a pop of color. These little garnishes make the dessert look like it came from a fancy restaurant!