Recipe by Earnest Ice Cream
Combine raspberries, 1/3 cup sugar, one tablespoon lemon juice, water, and balsamic vinegar in a saucepan over medium heat. Bring to a simmer and cook until sugar dissolves and berries collapse, two to three minutes. Remove from heat and strain into a bowl. Cool to room temperature, cover, and refrigerate until thoroughly chilled.
Combine two cups sugar, two cups water, two tablespoons lemon juice, and vanilla extract in a medium saucepan and bring to a simmer over medium heat.
Place peach halves with cut sides up in the syrup and simmer until tender, five to eight minutes per side, basting with the syrup occasionally. Remove from heat and allow to cool in the syrup. Transfer to a bowl, cover, and refrigerate until thoroughly chilled, about four hours.
Remove peach skins and serve each peach half on top of a scoop of Earnest Ice Cream in a bowl. Spoon the raspberry sauce over the top. Garnish with toasted hazelnuts.