Preheat your oven to 325 degrees Fahrenheit.
Generously butter a baking dish.
Cut the bread into 1 inch cubes; you should have 8-10 cups of bread cubes.
Whisk together eggs, milk, half and half and vanilla.
Add the sugar and whisk to combine.
Add the melted butter and whisk it into the egg mixture.
Put the cubed bread into your buttered baking dish and pour the egg mixture over the bread cubes.
Sprinkle the pecans over the top and bake in the oven for 1 hour until a nice golden brown.