Peel the oranges as if you're going to cut them into supremes -- like this. Then cut them into very thin slices and cut those into a super fine dice, and add them to a medium-sized mixing bowl.Now add the onion, cucumber and jalapeño pepper.Mix to blend and season to taste with sea salt and freshly ground black pepper. (Here's How to Season to Taste.) Set aside.In a small bowl, mix all of the spices and the salt together. Once they're blended evenly, pour the mixture on a large plate. Gently shake the plate to evenly spread the spices out.Gently press each shrimp into the spice mixture, coating both sides evenly.Place them on a clean plate as you go.Coat the bottom of a large sauté pan with the oil. Once the pan is very hot, add the shrimp, with ample space between them. Sauté the shrimp just until they're cooked through, about a minute per side.Arrange about 5 shrimp per serving plate, and then spoon the salsa over and around them.Serve!