Take your raisins and soak them in four cups of hot water until they plump up, about 30 minutes.
Alternatively, raisins can be soaked overnight in rum or whiskey. (If soaking overnight, the raisins don't have to be soaked in water).
Use an electric mixer to beat the white sugar, brown sugar, and the eggs until creamy. Gradually add the sweetened condensed milk and evaporated milk. Beat until frothy.
Add the melted butter, whole milk, cinnamon, nutmeg, and salt and beat until well blended.
Lightly butter a 9” x 13” pan. Arrange the bread cubes in the pan, scatter the plumped raisins among the bread, and slowly pour in the milk mixture
Bake in the oven for about one hour. You can tell its is done when the entire top puffs up and a knife inserted in the middle comes out clean.
If you don't like raisins, you don't have to add them. Proceed with the instructions - just omit the raisins.
Also, you can use prunes or dates instead of raisins.
You can use bread that is more than a 1 day-old for the recipe as well (2 - 5 days old).