Preheat the oven to 160° C w/ fan.
Grate the gruyere.
Cut the bread.
Oil 2 ovenproof bowls.
Add a layer of bread, soak w/ some wine & sprinkle w/ grated gruyere.
Add some butter on top.
Bake in the oven for about 10 min.
Serve immediately together w/ the greens.