Preheat oven to 200C. Bring stock and 40gm butter to the boil in a large frying pan over high heat, add witlof and sugar, season to taste, reduce heat to medium-high and turn occasionally until witlof is tender and stock is reduced (4-6 minutes). Transfer witlof and pan juices to a 20cm x 30cm baking dish and set aside.
Wipe out pan, add remaining butter, cook over medium heat until foaming, add shallot and garlic, stir occasionally until tender (5-10 minutes), add bacon and stir occasionally until very tender (8-10 minutes). Transfer to a bowl and set aside.
Combine breadcrumbs, milk, herbs and 70gm cheese in a bowl, add onion mixture, stir to combine and season to taste. Scatter over witlof and bake until golden (20 minutes), then scatter with remaining cheese and bake until bubbling (5-10 minutes). Serve hot.
This recipe is from the June 2012 issue of Australian Gourmet Traveller.