In a small bowl combine the pork, shallots, garlic, sugar, fish sauce and pepper. Stir to combine well, cover, and refrigerate for at least 1 hour and up to overnight. Transfer to the freezer for 30 minutes, or until the mixture is partially frozen.
Place the rice in a small skillet and heat over medium-high heat, stirring constantly, until rice is toasted, golden brown and fragrant. Transfer to a plate to cool. When cool, place rice in a coffee grinder and process to a fine powder. Measure 3 tablespoons of the powder and set aside. Save any remaining powder for another purpose or discard.
Transfer the partially frozen meat mixture to a food processor and process to a completely smooth but stiff paste. Add the pork fat to the processor and process until smooth or finely chopped. Add the roasted rice powder and pulse several times to combine the mixture. Do not over process or the mixture will become sticky.
Preheat a grill to medium-low.
Transfer the meat mixture to a small bowl. Lightly oil your hands. Divide meat mixture into heaping 1 1/2 tablespoonfuls and roll each into a smooth ball. Recoat your hands with oil, as necessary. Thread the meatballs onto the bamboo skewers, fitting as many as you can on each skewer.
Coat the grill lightly with oil and grill the skewered meatballs, turning occasionally, until cooked through, 20 to 30 minutes. Serve warm or at room temperature.