Matt Tebbutt served up tasty leek and mustard Welsh rarebit with mustard and brown sauce on Go Veggie and Vegan.
The ingredients are: 2 leeks, chopped finely, garlic clove, grated, 100g butter, 1 tbsp flour, 200ml milk, 200g cheddar cheese, 1 tbsp Dijon mustard, 1 tbsp vegan brown sauce (check labels of mainstream brands as some are suitable), 2 thick slices of sourdough bread, butter, 1 tbsp wholegrain mustard, pickled walnut and chives.
See recipes by Matt in his book titled: Weekend: Eating at Home: From Long Lazy Lunches to Fast Family Fixes available from Amazon now.