Heat the oils in a medium saucepan over medium heat. When hot, add the flour and cook, whisking for a minute or two, don’t let the roux brown, you want a nice blonde roux for your bechamel. Slowly pour in the milk while whisking constantly to avoid lumps. Cook, stirring for another 2-3 minutes until the mixture is smooth and thickened. Mix in the ham, cheese and nutmeg with a spoon until well incorporated and the mixture pulls away from the sides of the pan. Taste for seasoning. Spread the mixture out evenly in a small square 8x8 baking dish. Cover with plastic wrap, make sure the wrap is touching the top of the filling so a film doesn’t develop on top. Cool completely in the refrigerator, at least 2 hours or preferably overnight.
To make the aioli, place egg yolk, water, spice blend and vinegar in the bottom of an immersion blender cup. Pour oils on top. With the immersion blender at bottom of the cup whip ingredients, slowly tilting and lift the immersion blender until your aioli is formed. Transfer to a bowl and drizzle a little garlic oil and sprinkle a little more spice blend on top for presentation.
When ready to cook the croquetas, set up your breading station. Lightly beat the eggs in a shallow dish. Mix the breadcrumbs and paella blend in another dish. Use a disher or a tablespoon to portion the cooled filling and then form into balls. Using the “right hand-left hand method” (demonstrated in class). Dip each ball into the egg and then the breadcrumbs and then place on a baking sheet and return to the refrigerator for 20-30 minutes. You can do this ahead by a couple of hours but not overnight so the breading doesn’t get soggy.
Heat canola oil in a large, heavy bottomed pot over medium high heat until a drop of water spatters in the oil. Working in batches, fry the croquetas in the oil, turning them on all sides, until golden brown and crispy, about 2 minutes. Drain on paper towels. Transfer to a serving dish aside the aioli.