Preheat the oven to 350°F.
Lightly grease a baking dish with oil or nonstick cooking spray.
Cut the French bread into cubes.
Place the bread cubes in a large mixing bowl.
In a separate bowl, combine the whole milk, heavy whipping cream, sea salt, granulated sugar, vanilla extract, and slightly beaten eggs.
Whisk until the mixture is smooth and evenly combined.
Pour the custard mixture over the cubed bread.
Gently stir or press the bread down to ensure the pieces are evenly coated.
Allow the bread to sit for 10 minutes so it can absorb the custard.
In a separate bowl, combine the softened butter, chopped pecans, and packed brown sugar.
Mix until the ingredients are fully combined.
Spoon half of the soaked bread mixture into the prepared baking dish.
Spread it into an even layer.
Add half of the butter, brown sugar, and pecan mixture over the bread layer.
Spoon the remaining soaked bread mixture over the pecan layer.
Spread gently to distribute it evenly.
Top with the remaining butter, brown sugar, and pecan mixture.
Bake for 45 to 55 minutes, or until the edges are set and the center is slightly wobbly.
Remove the bread pudding from the oven.
Allow it to cool for at least 30 minutes before serving.
Serve warm.