Start by gently melting 1 cup of white chocolate chips using a double boiler method or microwave in 20-second bursts, stirring until smooth and creamy. Set aside to cool slightly but don’t let it harden.
Pour 1 cup of heavy cream into a chilled mixing bowl. Add 1 teaspoon of vanilla extract. Whip on medium-high speed until soft peaks form.
Carefully fold the melted white chocolate into the whipped cream using a spatula, keeping the mousse light and fluffy.
In a small saucepan, combine 2 cups fresh raspberries, 2 tablespoons sugar, and 2 tablespoons water. Heat over medium heat, stirring occasionally, until raspberries break down and sauce thickens (about 5-7 minutes). Remove from heat and cool. Strain through a fine mesh sieve for a smoother sauce if desired.
Spoon a layer of raspberry sauce into the bottom of each serving cup. Top with a generous dollop of white chocolate mousse. Repeat layers if cups are deep enough, ending with mousse on top.
Top each mousse cup with a swirl of whipped cream and garnish with fresh mint leaves. Chill in the refrigerator for at least 2 hours before serving.