Keeps 4 days refrigerated and freezes 3 months — a good freezer dish, since the peppers are already soft so texture loss doesn't matter. Reheat in a pan or covered in the oven.
No. Browning them and finishing them among the peppers cooks them through and keeps the flavour in the dish; boiling leaches it into the water.
Both are traditional — sweet is fennel-forward, hot adds chilli. Using half of each is common and gives more depth than either alone.
160°F internally, or no pink at the centre when sliced. Returning the slices to the pan for a couple of minutes finishes anything underdone.