Preparation
Wash the peppers, roast them, peel them, remove the core and inner seeds. Cut them into strips about a couple of inches wide. Put them in a pan with a few tablespoons of oil and let them brown for 5 minutes, stirring occasionally. Add the vinegar, sugar, salt and pepper. Cook over very low heat until the vinegar has completely evaporated and the peppers are softened, then add the pitted olives cut in half, capers, pine nuts and raisins, previously soaked in cold water for 10 minutes and squeezed. Leave to gain flavor for a few more minutes and then turn off the heat. In a separate pan, toast the breadcrumbs with a tablespoon of oil. Place the peppers in a serving dish, sprinkle with the toasted breadcrumbs and, if desired, with a few leaves of sage and a sprig of thyme.
Source https://www.ricettedellanonna.net/peperoni-in-agrodolce/