1.Discard the rind from the speck. Cut speck into 3cm pieces.
2.Heat half the oil in a large frying pan over medium-high heat; cook sausages and speck, turning, until browned all over. Transfer to a 4.5-litre (18-cup) slow cooker.
3.Cook lamb in same frying pan, in batches, over medium-high heat, until browned all over. Transfer to cooker. Drain fat from pan.
4.Heat remaining oil in same frying pan over medium heat; cook onion and bay leaf, stirring, for 5 minutes or until onion softens. Add garlic; cook, stirring, for 1 minute or until fragrant. Transfer to cooker.
5.Add tomatoes, paste, beans and the water to cooker. Cook, covered, on low, for 8 hours.
6.Just before serving, sprinkle cassoulet with parsley and, if you like, lightly toasted breadcrumbs.
There are many regional variations of cassoulet in France. For special occasions, you could add two confit duck marylands. Pan fry them until hot and browned all over, then place on top of the hot cassoulet before sprinkling with the parsley. Complete recipe to the end of step 5. Pack into freezer-proof containers, leaving a 2.5cm space to allow for expansion. Seal, label and freeze for up to 3 months. Thaw overnight in the fridge. Reheat in a saucepan or microwave on medium power (50%) until heated through, then continue from step 6.