French onion soup

Why has it been so long since I've made this oniony wonder? The inclination to throw everything into the soup pot at this time of year is a strong one; especially when there's a wealth of wintry root veg in season. Lest we forget that often, simplicity is best.

A small knob of butter
5 Large brown onions, thinly sliced
2 Bay leaves
A few sprigs of fresh thyme
2 Garlic cloves, finely chopped
A splash of dry sherry
500ml Beef or vegetable stock
2Tsp mustard powder
Salt and pepper
1 ciabatta loaf, sliced
Finely grated gruyere cheese

1 Melt the butter in a pan, before adding the thyme, garlic and bay. Stir gently for a few minutes, then add the onions. Soften gently on a medium heat for about 10 minutes.
2 Stir the mustard powder into the onions, add the sherry and then pour in the stock (I used vegetable stock in this instance - prefer beef though). Simmer on a relatively fast bubble for about 20 minutes.
3 Toast the ciabatta slices, then top with grated Gruyere. When ready to serve, spoon a portion of soup into a bowl, float a ciabatta on top and then grate in a bit more cheese for good measure. Pop under the grill for a few minutes, then serve.