Croquettes are one of my favorite appetizers because they are so easy to make, and everyone loves how the warm, crunchy-coated pieces just melt in your mouth. In Spain, croquettes come in many flavors: jamón serrano, chicken, fish, you name it — they're a national delicacy. They're also very popular in Brazil, so I had to give you my take on this savory classic given my love of both countries. The best part about this recipe is that it uses up your leftover chicken or rotisserie chicken. My mom even makes croquettes with leftover Thanksgiving turkey, stuffing and/or mashed potatoes.
Technique tip: You can freeze the formed, uncooked croquettes on a baking sheet, then put them gently in a resealable freezer bag and keep them frozen for up to 1 month. Remove and thaw in the refrigerator overnight, then fry when ready to serve. Or fry the croquettes ahead of time and reheat them in the oven at 325 degrees for 10-15 minutes.
In a medium saucepan, melt 4 tablespoons of the butter, then whisk in 1/2 cup of the flour. Whisk in 1/2 cup of the milk and the broth. Cook, whisking continuously, to thicken, 4-6 minutes, then remove from the heat and let cool for 10 minutes.2.
In a skillet, melt the remaining 1 tablespoon butter over medium heat. Add the onion and celery and cook, stirring, until lightly softened, about 2 minutes.3.
In a large bowl, mix the cooked chicken, onion-celery mixture, parsley, thyme, celery seeds (if using) and cayenne. Season with the salt and black pepper. Stir in the roux to make the croquette paste. Divide and form into about 16 sausage-like rolls, about 2½ by 1 inch; they will be a bit wet.4.
In a shallow bowl, whisk the eggs with the remaining 2 tablespoons milk. In a separate shallow bowl, mix the bread crumbs and remaining 2 tablespoons flour. Dredge the croquettes first in the egg and then roll in the bread crumb mixture. Arrange the croquettes on a baking sheet and refrigerate for up to 2 hours.5.
Preheat the oven to 250 degrees. Line a baking sheet with parchment paper.6.
In a deep skillet, heat about 1/2 inch of vegetable oil to 350 degrees — you'll know it's ready when you can drop in a bit of flour and it sizzles. Fry the croquettes in batches, rotating them on all sides until they are golden brown, 4-6 minutes total. As you go, transfer the fried croquettes to the prepared sheet pan and keep warm in the oven until all batches are done. Serve right away.