Add raspberries, honey, and lemon juice to a small saucepan over medium heat. Cook for 4–5 minutes, stirring often, until the berries break down and become saucy. Remove from heat and mash well. For a smoother mousse, strain the raspberry mixture through a fine mesh sieve to remove seeds. Let the puree cool to room temperature.
In a small bowl, sprinkle gelatin over cold water. Let it sit for 5 minutes to bloom. Once bloomed, microwave for 5–8 seconds or warm gently until dissolved. Do not boil.
In a medium bowl, stir together Greek yogurt, vanilla extract, cooled raspberry puree, and dissolved gelatin until smooth.
In a separate bowl, beat 1 cup heavy cream with 2 tablespoons powdered sugar until soft peaks form.
Gently fold the whipped cream into the raspberry yogurt mixture until fully combined. Be careful not to over-mix so the mousse stays light and airy.
Spoon mousse into small jars, cups, or dessert dishes. Cover and refrigerate for at least 2 hours, or until set.
Before serving, whip the remaining ½ cup heavy cream with powdered sugar and vanilla until soft peaks form. Top each mousse cup with whipped cream and fresh raspberries. Add mint, lemon zest, or white chocolate shavings if desired.