Preheat your oven to 350°F (175°C).
Slice the French bread into 1-inch thick slices and arrange in a greased baking dish.
In a large bowl, whisk together the eggs, milk, heavy cream, granulated sugar, vanilla extract, cinnamon, nutmeg, and salt.
Pour the egg mixture over the bread slices, making sure they are well coated. Cover and refrigerate for at least 2 hours or overnight.
In a small bowl, mix together the brown sugar, chopped pecans, and melted butter. Sprinkle this mixture evenly over the soaked bread.
Bake in the preheated oven for 45 minutes or until the top is golden brown and the custard is set.
Let it cool for a few minutes before serving.