Prep the berries. Rinse and hull the strawberries. Pat them dry so excess water doesn’t thin the mousse.
Blend the base. In a blender, combine strawberries, Greek yogurt, protein powder, honey or maple syrup, vanilla, salt, and lemon juice if using.
Blend until completely smooth, about 20–30 seconds. Taste and adjust sweetness.
Chill the mixture briefly. Pour the strawberry base into a bowl and place it in the fridge for 10–15 minutes. This helps it thicken slightly before folding.
Whip the cream. In a cold bowl, whip the heavy cream to soft-medium peaks.
Don’t overbeat; you want it fluffy, not stiff.
Fold gently. Using a spatula, fold the whipped cream into the chilled strawberry mixture in two additions. Work slowly to keep it airy.
Portion and chill. Spoon the mousse into small glasses or ramekins. Cover and chill for at least 1 hour, or up to 24 hours for a firmer set.
Garnish and serve. Top with sliced strawberries, a little shaved chocolate, or mint right before serving.