Start by peeling and cutting the onion into small cubes. Peel and chop the garlic clove into small pieces. Also, cut the bacon into ½ inch pieces.
In a large pan over high heat, cook the bacon for 10 minutes. Stir a few times to make sure the bacon cooks evenly and it doesn't burn. Remove from the pan onto a plate with a paper towel so it can absorb all the excess grease.
Lower the heat to medium high and add the onion. Cook for 5 minutes while stirring occasionally so it can brown evenly. Add the flour and quickly start stirring so the fat and the flour can get incorporated. Cook for 2 minutes.
Slowly pour the milk while you stir. Make sure that all the milk you pour is completely incorporated before you add more. Cook for 8 minutes and stir constantly.
Add the bacon, parmesan cheese, and salt, and stir. Let the pan cool at room temperature and then cover with plastic film by placing it directly on top of the mix. Place the mix in the fridge and let it cool for at least 4 hours
Remove the mix from the fridge to form the croquetas. Take about 4 tablespoons of the mix and shape the dough into a ball or the shape you like (*see notes). Put the croquettes in the fridge to cool for at least 30 minutes.
In a small dish, beat your two eggs. In another dish, add your breadcrumbs. Pass each ball first through the beaten egg and then pass the ball through the breadcrumbs. Make sure that each ball is completely covered. Do this by lightly pressing the breadcrumbs on each ball.
Put the croquettes back in the fridge so they can firm up before frying. This will prevent them fromjbreaking while frying.
In a medium size pan, add the oil over high heat. Once the oil is hot, add the balls to fry for 2 minutes or until golden brown. Do not overcrowd the pan. Make sure to flip the balls around so they can cook evenly. Serve immediately. Buen provecho!
Notes
Bacon- I used bacon, but ham is also very popular when making croquetas.
Cooling time- The cooling time is very important, especially if is a hot day.
Shaping- I shape the croquetas into balls the size of a golf ball. But you can make them smaller. Or you can give them a more cylindrical shape like the sorullitos de maiz.
Freezing. First, place the croquetas on a flat plate or tray so they can get firm. Then you can transfer them into an airtight container or, best to use a freezer bag. When ready, you can fry from frozen.