1. Combine first 3 ingredients in a large shallow bowl. Combine flour and cornstarch in a separate large shallow bowl.
2. Pour oil to depth of 1 inch in a deep skillet or Dutch oven; heat to 350° to 360°.
3. Place snapper in flour mixture, coating both sides and shaking off excess. Dip snapper into egg mixture and then back into flour mixture, shaking off excess.
4. Place immediately into hot oil, and fry 3 minutes on each side or until golden brown and crispy. Serve immediately over hot cooked rice with Nuoc Nam, mango, and jalapeño.