Rose-geranium leaves infuse this ice cream with a wonderful floral aroma and citrus-herb flavor.
Combine cream, milk, geranium leaves, and cardamom pods in a saucepan; cook over medium-high heat, stirring occasionally, until mixture is scalding hot (do not let simmer), about 2 minutes. Remove from heat. In a large heatproof bowl, whisk yolks with sugar and salt until smooth and pale. Whisking constantly, ladle half of cream mixture into yolk mixture, a little at a time, until combined. Whisk yolk-and-cream mixture back into saucepan with remaining cream mixture. Cook over medium heat, stirring constantly, until thick enough to coat the back of a wooden spoon and a thermometer registers 180 degrees, 5 to 7 minutes.
Pour custard through a medium-mesh sieve into a bowl set in an ice-water bath. Let cool completely, stirring frequently, about 10 minutes.
Churn custard in an ice cream maker (following manufacturer's instructions) until it has texture of soft-serve ice cream. Freeze in an airtight container until firm, at least 4 hours and upto 1 month. If ice cream is frozen solid, transfer to refrigerator to let soften slightly before serving, about 20 minutes. Serve, with peaches and cookies.