In a saucepan, melt the butter over medium heat. Add the flour and cook, stirring constantly, for about 2-3 minutes to form a roux. Do not let it brown.
Gradually whisk in the milk and broth, continuing to cook and stir until the mixture thickens and becomes smooth.
Stir in the shredded meat, chopped onion, nutmeg, salt, and pepper. Cook for another 5-7 minutes until the mixture is thick and the meat is well combined.
Transfer the mixture to a bowl and let it cool to room temperature. Once cooled, chill it in the refrigerator for at least 1 hour to firm up.
Once the mixture is chilled, shape it into small logs or balls. Roll each piece in the breadcrumbs, then dip it into the beaten eggs, and coat again with breadcrumbs.
Heat oil in a deep fryer or large skillet to 350°F (175°C). Fry the kroketten in batches until golden brown and crispy, about 3-4 minutes. Drain on paper towels.
Enjoy your meal!