Heat 2 tablespoons of vegetable oil in a large pan over medium-high heat. Once hot, add the cooked egg noodles, spreading them into an even layer. Allow to cook undisturbed until the bottom is browned and crispy. Carefully flip to brown the other side while keeping the cake shape intact. Remove and set aside.

In a separate pan over medium-high heat, melt 1 tablespoon of unsalted butter. Add the shrimp with 1 teaspoon garlic salt. Cook until the shrimp turn pink and opaque, approximately 2-3 minutes per side. Remove and set aside.

Add 1 tablespoon of oil to the same pan. Add bok choy, mushrooms, zucchini, carrots, and onions. Stir fry over medium-high heat until vegetables soften but remain crisp, about 2-3 minutes. Remove and set aside.

In a saucepan over medium-high heat, combine chicken stock, oyster sauce, soy sauce, sugar, sesame oil, salt, and pepper. Bring to a simmer.

In a small bowl, whisk together cornstarch and water. Slowly pour into the simmering sauce while whisking continuously until thickened.

Return stir-fried vegetables to the pan and add shrimp. Pour the thickened sauce over everything. Toss to coat evenly.

Place the crispy noodle cake on serving plates and spoon the stir fry over it. Serve immediately.