Cajuns didn't celebrate St. Patrick's Day traditionally, although there were enough Irish in New Orleans to celebrate that holiday from early on. But they did have a holiday where the rules of Lent were lifted for a day, and that was St. Joseph's Day, March 19.
March 19 always falls during Lent and, according to Roman Catholic canon law, if the feast day falls on a Friday, the obligation to abstain from meat or do penance is lifted.
Apparently, it's even a bigger deal in Italian homes, where elaborate altars are constructed and decked out with festive breads and desserts. Anyone can come by and eat, and offer their prayers and donations.
We always had pain perdu, literally "lost bread," which the English call French toast, on that day, and usually steak that evening. My mom always made it with old bread, the better to soak up the egg mixture, and then griddled it. This version is easier if you want your whole family to eat at once, and you can make it the night before, so it's ready to go in the morning.
Baked French Toast
12 slices thick French bread (not sourdough)
3 cups 1 percent milk
1 teaspoon vanilla
1/4 teaspoon salt
3 tablespoons sugar
Butter (for baking dish)
Cinnamon (for sprinkling)
Combine milk, eggs, vanilla, salt and 2 tablespoons sugar; mix well. Arrange bread in one layer in a pan and pour the mixture evenly over all the slices. Cover and put in the refrigerator overnight.
In the morning, set oven to 425 degrees with a rack in middle position. Butter a 13x9-baking dish and transfer the slices to it. If there is any remaining liquid, pour it on top.
Mix about a 1/2 teaspoon of cinnamon with the remaining tablespoon of sugar and sprinkle top evenly with it. Place baking dish on the middle rack and bake until center of each slice is set and top is golden brown, 30 to 35 minutes. Serve with Louisiana cane syrup, maple syrup, powdered sugar or fresh berries.