Chicken and Cured Ham Croquettes

In a medium saucepan over medium heat, combine the unsalted butter and 5 tablespoons of premium olive oil, heating them until the butter melts.
Add the all-purpose flour and cook, stirring constantly, for approximately 3 minutes.
Gradually blend in the milk and broth, season with salt, pepper, and a pinch of nutmeg, and continue cooking, stirring constantly, until the sauce becomes thickened and velvety.
Stir in the finely chopped chicken and Serrano ham or prosciutto, continuing to stir until the sauce reaches a gentle boil, approximately 10 minutes more.
Let the mixture cool, cover it, and refrigerate it for at least 3 hours.
(The croquettes can be prepared to this point and refrigerated for up to one day in advance.
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On a lightly floured work surface, shape the chicken mixture into charming 1-inch balls (approximately 1 tablespoon each), using floured hands.
Prepare separate shallow bowls for the eggs and bread crumbs.
In a large skillet, heat at least 1 inch of extra-virgin olive oil over medium-high heat (or for the best results, use a deep fryer set at 365°F) until a cube of bread turns a seductive golden brown in just 60 seconds.
Dip each croquette in the beaten egg and then generously coat them with the bread crumbs.
Fry the croquettes, turning them several times, until they achieve a luscious golden hue.