Peel and halve a garlic clove and cook it with the split peas in the stock for 40 minutes. Check the seasoning and leave to cool slightly.
Meanwhile, lightly spray a roasting tin with oil. Put the remaining garlic cloves in the tin with the peppers and onion and cook in a preheated oven, 200°C (400°F), Gas Mark 6, for 20 minutes. Squeeze the roasted garlic cloves from their skins and chop with the roasted vegetables.
Mix the split peas with the roasted vegetables, mint and capers. Flour your hands and shape the mixture into patties. Refrigerate until ready to cook.
Heat a frying pan and spray with oil. Cook the patties, in batches if necessary, leaving them to cook undisturbed for 2 minutes on each side. Serve either hot or cold, garnished with mint leaves, with tzatziki or raita on the side.