
In a medium bowl, combine the ingredients to marinade; add chicken, cornstarch, all-purpose flour, beaten egg, soy sauce, red chili powder, salt, and pepper. Allow the chicken to marinade for at least 30 minutes.
Deep fry the chicken pieces in batches until golden and crispy. Drain the excess oil and set it aside. Repeat the same with the remaining chicken pieces.
Heat a large skillet with oil to prepare the sauce. Add ginger, garlic, and bell peppers. Saute for 3-4 minutes. Add in the sauces; soy sauce, red chili sauce, and tomato ketchup. Simmer for a minute.
Add the cornstarch slurry (1 teaspoon cornstarch + 2 tablespoons) to the sauce and cook until the sauce starts to thicken.
Add in the fried chicken pieces and toss well with the sauce to coat well. Remove the skillet from the heat and garnish with chopped green onions.
Serve the chicken Manchurian over the bed of white rice to enjoy.