Place breadcrumbs, parsley, anchovies, capers, garlic, oil, cayenne and salt in a bowl. Juice and zest 1 lemon, add to the bowl and mix well.
Half fill a large bowl with cold water and squeeze half of the remaining lemon into it, place the other half alongside.
Trim stems of artichoke, leaving about 3cm attached. Working one artichoke at a time, remove outer leaves until a green-yellow base appears. Using a small paring knife, peel stems and trim the dark green from the artichoke base. Cut off top third of the artichoke. Gently ease the leaves apart and, using a teaspoon, scoop out and discard the hairy choke from the centre. Rub cut surfaces with the lemon half and place prepared artichoke in the lemon water. Repeat with remaining artichokes.
Remove artichokes from the water and place upside down on a clean tea towel to drain.
Preheat oven to 200°C.
Fill the centre of each artichoke with the breadcrumb mixture, packing extra mixture between the leaves.
Arrange artichokes in one or two wide heatproof bowls and place in a baking dish. Pour boiling water half way up the side of the baking dish, cover the baking dish tightly with foil and bake for about 30 minutes, until the base of the artichokes are tender when pierced with a thin skewer or toothpick. Remove foil and cook for a further 5 minutes.
Serve with finger bowls, large serviettes and a large bowl for discarded leaves.