An open-faced baguette sandwich topped with cheese and mushrooms and toasted in the oven. Finish it with a squeeze of ketchup and some crisp fried onions.
Halve the bread lengthways and place each half with the cut facing up. Spread the butter on all halves.
Thinly slice the mushrooms and top the bread halves with an even layer of mushrooms.
Grate the cheese and add it over the mushrooms making sure to cover the whole length of the bread.
Toast in the preheated oven at 200°C (390°F) for 10 minutes, until the cheese melts and the bread gets nicely toasted.
Squeeze the ketchup in a zig-zag pattern over the sandwiches, top with minced chives and crisp fried onions if desired.