- Step 1
Place flour and shanks in a large snap-lock bag. Season with salt and pepper. Seal. Shake to coat.
- Step 2
Heat half the oil in a large, heavy-based saucepan over high heat. Cook shanks, in batches, turning, for 4 to 5 minutes or until browned. Transfer to a plate.
- Step 3
Reduce heat to medium-high. Heat remaining oil in pan. Add onion, garlic, carrot and celery. Cook for 3 minutes or until onion has softened. Add tomato paste. Stir to combine. Add wine, tomato and stock. Stir to combine.
- Step 4
Add shanks. Cover. Bring to the boil. Reduce heat to low. Simmer for 1 hour 30 minutes.
- Step 5
Remove lid. Add zucchini. Simmer for 30 minutes or until meat is tender and falling off the bone. Season with salt and pepper.
- Step 6
Serve lamb shank casserole with soft polenta or mash.
Prepare in advance: Follow recipe until the end of step 3. Cool. Store casserole in an airtight container. Refrigerate for up to 3 days or freeze for up to 3 months.