Preheat your oven to 375°F (190°C).
Grease a baking dish with butter.
In a saucepan, melt the butter over low heat.
Add the onion juice and cook slowly for about 5 minutes until softened.
Add the flour to the saucepan and stir until well mixed.
Gradually pour in the milk, stirring constantly until the mixture thickens to a creamy consistency.
Season the sauce with salt and pepper to taste.
Pour the creamy sauce into the prepared baking dish, spreading it evenly.
Carefully crack the eggs over the sauce, ensuring they are evenly distributed.
Sprinkle the bread crumbs over the eggs and dot with butter.
Bake in the preheated oven for 3-4 minutes until the egg whites are set but the yolks are still runny.
Remove from the oven and let it cool slightly before serving.
Serve your delicious Creamy Lyonnaise Baked Eggs hot, straight from the oven.