Croquetas de Jamón Serrano Recipe - Traditional Spanish Ham Croquettes

Name: Croquetas de Jamón Serrano Recipe - Traditional Spanish Ham Croquettes
Prep time: 30 min
Cook time: 15 min
Total time: 45 min
Cuisine: Spanish
Ingredients: 4 tbsp unsalted butter ((60 g)); ¼ cup olive oil ((60 ml)); 1 scant cup flour ((just under one cup -- 120 g)); 1 medium onion (very finely diced); ¼ gallon whole milk (at room temperature (1 liter)); 1 pinch nutmeg; ½ pound jamón serrano (diced into small pieces (225 g)); flour (for breading); 2 beaten eggs; bread crumbs (for breading (try Panko for non-traditional extra crispy croquettes!))