Corned beef with mustard sauce

• oil, for greasing
• 1500 g water
• 4 whole cloves
• 50 g malt vinegar
• 900 - 1200 g corned beef silverside
• 400 - 500 g Kent pumpkin, peeled and cut into pieces (5-6 cm)
• 150 g frozen green peas
• 150 g frozen corn kernels
• 300 - 400 g sauerkraut, drained (see Tip)

Mustard sauce

• 30 g unsalted butter
• 30 g plain flour
• 300 g milk
• ½ - 1 tsp salt, to taste
• 1 tsp wholegrain mustard
• 1 ½ tsp mustard powder