Stale bread soaked in egg and milk, then pan-fried to a golden crust — called *pain perdu* (lost bread) in France because it rescues bread past its prime; topped with maple syrup, fruit, or icing sugar.
Pain perdu
In France the dish is pain perdu — lost bread — so named because it rescues bread that would otherwise be lost (thrown away). Medieval French households soaked stale bread in a mixture of egg and milk to revive it. The 15th-century cookbook Le Ménagier de Paris contains an early version. The name “French toast” appears in English texts from the 18th century, likely reflecting the French origin of the technique for English speakers.
Why stale bread
Stale bread is structurally preferable to fresh bread for this preparation. Fresh bread is too soft and collapses when soaked in the egg mixture, producing a soggy interior. Stale bread has lost enough moisture to absorb the custard evenly without disintegrating, producing a custardy interior and crisp exterior after frying.
The custard ratio
Restaurant-quality French toast uses a higher cream-to-milk ratio and multiple egg yolks for a richer, silkier custard. Brioche or challah — enriched breads with high fat content — absorb the custard better and caramelise more evenly than plain sandwich bread.
Savoury French toast
Outside the sweet breakfast context, French toast exists in savoury forms: France’s croque-monsieur is essentially the same technique applied with ham and cheese. Spain’s torrijas are the Catholic Lent version, often soaked in wine rather than milk.