¾ cup sugar
6 large ripe peaches halved, pits removed
1 vanilla bean, split lengthwise or 1 teaspoon of vanilla extract
3 sprigs mint
1 tablespoon fresh lemon juice
Sprinkle sugar evenly across bottom of a large straight-sided pan or cast iron pot and place peaches, cut sides up, in a single layer on top. Scrape in vanilla seeds and add pod; scatter mint. Pour in cold water to come halfway up sides of peaches. Bring to a very, very gentle simmer over lowest heat, stirring liquid lightly once or twice to dissolve sugar and blend flavours. Cook peaches, turning once, until almost tender but not falling apart, 5–10 minutes. Let cool completely.
Pluck out vanilla pod and mint from pot; discard. Stir in lemon juice. Remove skins from peaches (they should slip off easily).
When cool refrigerate peaches in glass jar covered in their liquid.