Heat the olive oil in a fry pan, add the capsicum, paprika, cayenne pepper and a squeeze of lemon juice. Stir for 1-2 minutes until fragrant. Pour in the passata and simmer for 20 minutes or until thick. Blend with a stick blender.
Roast the potatoes for 30-45 minutes until golden and crisp.
Spoon the sauce over the potatoes. Sprinkle with parsley. Serve with a dollop of aioli or mayonnaise.