Step 1

Preheat oven to 180°C. Season half the flour, then toss with the lamb to coat. Heat 2 tbs oil in a large flameproof casserole over medium-high heat. Shake excess flour from the lamb, then cook, in batches, for 4-6 minutes, turning, until browned on all sides. Remove from pan.

Step 2

Reduce heat to medium and add remaining 1 tbs oil to the pan. Cook onion and celery, stirring, for 3-4 minutes until softened. Stir in tomato paste and cook for 1 minute. Return lamb to the pan with mushrooms, ale, consomme, bay leaf, sugar and Worcestershire. Season and bring to a simmer. Cover pan and bake in the oven for 11/2 hours or until lamb is tender, then remove from the oven.

Step 3

Mix remaining 1/4 cup (35g) flour with 1/2 cup (125ml) of the cooking juices in a separate bowl until smooth, then add to the casserole and stir to combine. Bring to a simmer and cook over medium heat for 3-4 minutes until sauce thickens.

Step 4

Spread mustard on baguette slices and layer on top of lamb mixture. Sprinkle with cheese and bake for 20 minutes until bubbling. Sprinkle with parsley, to serve.