Grease an 8-inch cast iron skillet (or an 8-inch baking dish) and set aside.
Cut bread slices into 1-inch cubes and place them in an even layer into a prepared skillet (or preferred baking dish). Sprinkle with raisins, or preferred dried fruit if desired.
In a large bowl, whisk eggs and sugar. Add milk, heavy cream, ground cinnamon and vanilla extract, and whisk until combined. Pour cream mixture over bread mixture in the prepared skillet or baking pan, making sure all of the bread is coated. You can use a spatula to press pieces down into the mixture to make sure that they are fully coated. Drizzle melted butter on top. Allow the bread to sit and soak up the mixture for about 30 minutes, but if you're in a hurry, bake it right away.
Preheat oven to 350°F/175°C. Bake for 40-45 minutes or until custard has set and the top is golden brown, or when a knife inserted in the center comes out clean. Let the pudding cool slightly before serving.
Bread pudding can be served warm or cold and will freeze well for up to 3 months.