Thoroughly mix flour, oil, water and salt to make a dough (add a bit more flour if needed so the dough is not sticky) and roll out as thin as possible.
Melt the butter in a pan, add onions and sweat for just a couple of minutes. Add bacon, stir and cook through.
Spread creme fraiche on top of dough, then spread onions and bacon on top of it. Season with salt and pepper as desired.
Put in the oven and bake for about 10-15 minutes. Once the bread looks crispy it's done.
