Bloom the gelatin. Sprinkle the gelatin over 3 tablespoons of cold water in a small bowl. Let it sit for 5–10 minutes until it looks thick and spongy. This step is key for a smooth, set mousse.

Warm the gelatin. Gently heat the bloomed gelatin in the microwave for 10–15 seconds or in a small saucepan over very low heat until fully dissolved. Do not boil. Set aside to cool for 1–2 minutes.

Make the raspberry puree. Add raspberries, lemon juice, sweetener, and a pinch of salt to a blender. Blend until smooth. Taste and adjust sweetness—you want it slightly sweeter than you think, since chilling softens sweetness.

Strain (optional but recommended). Press the puree through a fine-mesh sieve to remove seeds. You’ll get a silkier mousse and a prettier finish.

Whisk the base. In a large bowl, whisk Greek yogurt and vanilla until smooth. Slowly stream in the warm, dissolved gelatin while whisking steadily. This prevents clumps and helps the gelatin distribute evenly.

Combine. Pour the raspberry puree into the yogurt mixture and whisk until fully blended and uniformly pink. The mixture should be glossy and slightly thick.

Lighten the texture (optional). For extra airiness, whisk vigorously for 30–45 seconds, or use a hand mixer on low for about 30 seconds to add a bit of lift without overmixing.

Chill to set. Divide into ramekins, glasses, or jars. Cover and chill for at least 2 hours, or up to overnight. The mousse firms as it chills.

Garnish and serve. Top with fresh raspberries, a few chocolate shavings, or a sprinkle of toasted almonds. Serve cold.