Prep the strawberries: Add sliced strawberries to a bowl. Sprinkle with half the sweetener and a tiny pinch of salt.
Use a fork to gently mash about half the berries so they release some juices, leaving the rest in small pieces. Set aside for 5 minutes.
Chill your tools: For best results, place your mixing bowl and beaters in the freezer for 5 minutes. Cold equipment helps the cream whip quickly and hold its shape.
Whip the cream: Add cold heavy cream, remaining sweetener, and vanilla to the chilled bowl.
Beat on medium-high until soft peaks form. Don’t go past stiff peaks or the texture can turn grainy.
Fold in flavor: If using lemon zest, fold it into the whipped cream. The zest brightens the berries without adding carbs.
Combine gently: Spoon about two-thirds of the mashed strawberries into the whipped cream.
Use a spatula to gently fold, leaving streaks for a marbled look.
Layer and serve: Divide the mixture into 4 small glasses or bowls. Top with the remaining strawberry mixture for a pretty finish.
Chill briefly (optional): Refrigerate for 15–30 minutes to set and develop the flavors. It’s also great right away.
Garnish and enjoy: Add a small mint sprig or a few extra strawberry slices on top.
Serve cold.