Bloom the gelatin: In a small bowl, sprinkle gelatin over cold water. Let it sit 5 minutes to absorb.
Warm and dissolve: Microwave the bloomed gelatin for 10–15 seconds until fully melted (or warm gently on the stove).
Set aside to cool slightly.
Mash the raspberries: In a medium bowl, lightly mash the raspberries with 1 tablespoon sweetener. You want a saucy texture with some chunks left.
Mix the chocolate base: In another bowl, whisk Greek yogurt, protein powder, cocoa powder, remaining sweetener, vanilla, and salt until smooth. If using, add espresso powder or almond extract.
Melt the chocolate: Microwave the chopped dark chocolate in 15-second bursts, stirring between, until just melted and glossy.
Combine: Whisk the melted chocolate into the yogurt mixture until fully blended.
Add gelatin: While whisking, slowly stream the melted gelatin into the chocolate-yogurt mixture.
Whisk until smooth and slightly thickened.
Fold in raspberries: Gently fold in the mashed raspberries, leaving pretty streaks or fully mixing—your call.
Chill: Spoon into 4 small glasses or ramekins. Refrigerate for at least 1 hour, or until set and mousse-like.
Serve: Top with extra raspberries. For a glossy finish, dust with a touch of cocoa or shave a little dark chocolate on top.