Roast Beef

14 oz beef chunks, on the bone

3/4 teaspoon salt
1 teaspoon mustard powder
1 teaspoon paprika
1 teaspoon coriander powder
1 teaspoon cumin powder
1 teaspoon cinnamon
1/2 teaspoon cayenne pepper
1/2 teaspoon turmeric
3 cloves, crushed
4 peppercorns, crushed
1 1/2 teaspoons ginger, minced
3 garlic cloves, minced
1 tablespoon barbecue sauce
1 tablespoon lemon juice
2 tablespoons butter, melted

1 cup water
2 teaspoons corn starch