1. Mix together wheat flour, baking powder and water. Stir until mixed well, then add prepared shrimps. Set aside.
2. Heat oil in a wok over medium heat. Add shrimps (already dip in flour mixture) and fry until golden and crispy. Remove, drain and set aside.
3. Grind chopped garlic, coriander roots, and black peppercorns in a mortar and pound until mixed thoroughly (or using food processor). Then heat oil in a wok over medium heat and add the ground mixture and roasted chili paste. Stir fry until golden and aromatic.
4. Add egg yolk sauce, pepper and deep fried shrimp, and season with salt and sugar. Turn up to high heat. Stir quickly until all ingredients mixed well. Remove from heat.
5. Transfer to a serving plate. Serve immediately with hot steamed rice.