Heat the oil in a large pan. Sweat the onions, peppers, carrots and garlic in it for 5 minutes. Stirring occasionally. Add the apple and curry powder and leave to sweat for 4 minutes. Add the barley and chicken broth, bring to the boil. Reduce the heat and simmer for 15 minutes.
Put everything in an ovenproof container (preferably with a lid) and distribute the chicken breasts on the barley mix. Season with salt and pepper and bake with the lid (or covered with aluminum foil) at 190 ° C for 45 minutes.
Remove the lid or foil and spread the mango chutney (or the jam) on the chicken and bake for another 15 minutes (without the lid). Let stand 5 minutes before serving.