Beefy cheese melts

1 Melt the butter in a pot and pour a little out to brush the outside of the bread.

2 Place the sliced onions in the butter and cook slowly with a lid over a low heat for 15 minutes.

3 Remove the lid, turn up the heat, add a pinch of sugar and cook until they turn golden. Add salt and pepper and reserve.

4 Fold any leftover beef into the onions.

5 Brush two slices of bread with the Dijon mustard, spread the onion and beef mix on top, followed by the cheese.

6 Sandwich with the other slices of bread. Brush with some of the remaining butter on the outside.

7 Place the sandwiches butter side down on a moderately heated frying pan. Then brush the top of the slices. Cook until golden, then flip over and brown and crisp the other side, making sure the filling is soft and gooey.