Slice Spam into sushi-sized squares.
In a bowl, mix together equal amounts of soy sauce and brown sugar, then add minced garlic. Marinate the Spam for at least 30 minutes.
Prepare 2 cups of white sushi rice (also called glutenous rice or sticky rice) according to directions. When it's finished, mix together 3 tablespoons rice wine vinegar, 2 tablespoons sugar and 2 teaspoons salt, then mix this into the rice. Stir the rice frequently until it is cool enough to handle.
Remove the Spam pieces from the marinade and pat dry. Fry the Spam in olive oil until browned on both sides. Remove from the pan and set aside to cool.
Cut a sheet of nori into 1/2 inch (13 mm) wide strips.
Moisten your hands (they should be damp, not dripping wet), then mold the rice into blocks the same size as the Spam slices.
Place a Spam slice on a block of rice, then wrap a strip of nori around the middle (width-wise or length-wise). Moisten one end slightly to make it stick to itself.
Serve with the remaining marinade for dipping.