Cut the white bread into slightly thicker (approx. 8) slices the evening before. Leave to dry overnight in a slightly opened bag.
Do not cut the edges. Whisk the remaining ingredients in a shallow bowl. Poke holes in the slices with a fork so the mix can absorb better and faster. Let the slices stand until they are soaked. May take a few minutes. Melt the butter in a non-stick pan and fry the bread lightly brown on both sides, about 2-3 minutes on each side. If it gets too dark, reduce the heat so that the egg mixture in the middle of the slices can set. Arrange on a warm platter.
This goes well with maple syrup, honey, fruit spread or chocolate cream. If you want, you can spread some butter on the toast.