Cut capsicums in half and place under preheated grill for approximately 6 minutes until slightly blackened. Remove outer skin with flat knife and slice into long thin strips.
Heat olive oil in large shallow saucepan. Dice tomatoes finely and fry in olive oil until they become pulp.
Add basil, salt, pepper and saffron then stir in roasted red capsicums. Add cream and reduce to low simmer.
Bring water to boil with sea salt. Add pasta and cook according to instructions. Drain pasta well and leave in container to stand.
Fold the prawns and cooked pasta into the sauce then return to full heat for 2 minutes. Reduce to simmer. Don't leave prawns on heat for too long as they wilt and shrink. Just enough to warm them through.