50 g butter
1 tablespoon olive oil
1000 g onions - peel, cut in half and thinly slice
4 cloves garlic - peel and finely grate
2 tablespoons plain flour T55
250 ml dry white wine
1250 ml beef broth
8 slices baguette - cut into slices of 2 centimetres
140 g gruyère cheese - finely grate
salt - to your taste
black pepper - freshly ground from a pepper mill, to your taste
200 °C
