In a bowl, combine egg white and cornstarch. Whisk until frothy. well.
Add shrimp and coat evenly. Marinate for about 10 to 15 minutes and drain well.
In a bowl, combine stir-fry sauce ingredients: water, soy sauce, oyster sauce, Chinese cooking wine, brown sugar, and the 1 teaspoon cornstarch. Whisk until smooth. Set aside.
In a wok or wide pan over high heat, heat 2 tablespoons of the oil. Add shrimp and cook until the color changes to pink. Remove from pan and keep warm.
Remove excess oil except for about 1 tablespoon. Add onions and garlic and cook until softened.
Add carrots and celery and cook, stirring regularly, for about 30 to 40 seconds or until half done.
Add stir fry sauce (make sure to stir first to disperse cornstarch) and bring to a simmer until slightly thickened.
Add green peas and shrimp. Continue to cook, stirring to combine, for about 3 to 5 minutes or until green peas and shrimps are heated through and vegetables are tender yet crisp.
Add roasted cashews and gently toss to combine.
Season with salt and pepper to taste. Serve hot.