1. Measure 3 to 4 ounces uncooked shrimp-flavor crackers (krupuk; about 1 1/2 cups 2-in.-wide rounds, or 12 rectangular pieces 4 1/2 by 1 1/2 in.).
2. In a wok (at least 14 in.) or 5- to 6-quart pan, pour salad oil to a depth of about 1 1/2 inches. Set pan over high heat and bring oil to 350° on a thermometer. Adjust heat to maintain oil temperature.
3. Drop 3 to 5 rounds or 1 rectangular cracker into oil and, with a slotted spoon, turn to cook other sides; they puff almost immediately. At once, lift from oil and drain in paper towel-lined pans. Repeat step to cook remaining krupuk.