In a medium bowl, combine ½ cup of strawberry jam, 1 tablespoon of balsamic vinegar, and ¼ cup of water. Mix vigorously until smooth.

Wash, hull, and chop 1 cup of fresh strawberries, setting aside small pieces for filling and some for garnishing.

In a heatproof bowl, whisk together 3 egg yolks and ¾ cup of powdered sugar over simmering water until pale and frothy (4-5 minutes). Mix in 8 ounces of mascarpone and 1 teaspoon of vanilla until smooth.

Beat 3 egg whites to soft peaks, gradually add ¼ cup of powdered sugar until stiff peaks form (3-5 minutes).

Gently fold whipped egg whites into the mascarpone mixture and add ½ cup of chopped strawberries.

Dip each ladyfinger in the syrup for a couple of seconds. Layer them in a dish, followed by half the mascarpone mixture, then repeat with remaining ladyfingers and filling.

Cover with plastic wrap and refrigerate for 10-12 hours.

Garnish with reserved strawberries, slice into squares, and serve chilled.