Choose bread for the soak
Slightly stale, moderately thick bread absorbs custard without collapsing as quickly as very fresh thin bread. Rich breads brown readily, while sturdy loaves need a longer soak. The ideal choice depends on whether you want a soft centre or a more defined slice.
Mix a smooth custard
Beat eggs with milk and seasoning until no ropes of white remain. Use a shallow dish and turn the bread so both sides absorb evenly. A short soak coats the surface; a longer one reaches the centre but demands stronger bread.
Brown without scorching
Cook in a thin film of butter, oil or both over medium heat. If the outside colours before the centre heats, lower the temperature and allow more time. Thick slices can finish briefly in the oven after browning.