Cut the red pepper in half, discard the seeds and stem, chop the flesh into the smallest pieces possible.
Peel the garlic and ginger and chop together, finely.
Put all these ingredients into a saucepan and strain in the lemon and orange juice. Stir in the vinegar and spices and cover the pan.
Place over a fairly low heat and let the liquid barely simmer for 8-10 minutes, until the carrots are just soft but still have a slight resistance.
Remove from heat, cover the pan and leave until cold.
Meanwhile, chop the mint leaves, finely. When the carrots are cold, stir in the chopped mint followed by the olive oil. Season to taste and turn into a serving dish just before serving. Garnish with whole mint leaves.