Preheat the oven to 375°F and line a baking sheet. Toss the hulled and halved fresh strawberries with 1/4 cup of the granulated sugar and the aged balsamic vinegar, then spread in an even layer.

Roast for 30-35 minutes at 375°F until deeply caramelized and jammy. Cool the roasted strawberries, then puree until smooth and set aside.

In a saucepan, heat the heavy cream and whole milk until steaming but not boiling. Meanwhile, whisk the egg yolks with the remaining 1/4 cup granulated sugar until slightly thickened and paler.

Temper the yolks by whisking in the hot cream-milk mixture slowly. Return everything to the saucepan and cook, stirring constantly, until the custard reaches 175°F and coats the back of a spoon (visual cue: a clear line remains when you run a finger through).

Strain the custard into a bowl, then stir in the roasted strawberry puree, vanilla extract, and salt. Mix until fully smooth and evenly colored.

Cool completely over an ice bath until no longer warm to the touch. Refrigerate for 4 hours, covered, until thoroughly chilled (visual cue: cold all the way through).

Churn the custard in an ice cream maker according to the manufacturer’s instructions, until thickened to soft-serve consistency. Transfer to a container and freeze until firm.