Cook the egg noodles or udon noodles, drain and keep aside.
In a small bowl, add soy sauce, oyster sauce, tomato paste, sugar, salt and pepper. Stir all ingredients together until mixed well. Keep the sauce aside.
Heat oil in a pan.
Add sliced onion and minced garlic to pan and saute for a few minutes until the aroma comes and the onion becomes transparent.
Add prawns to the pan. Cook this for a few minutes until they cooked well. Remove the prawns from the pan and keep them aside.
In the same pan, add chopped tomatoes, sliced red bell pepper and carrot. saute this for a few minutes until all vegetables turn soft and crispy.
Add cooked noodles and sauce mixture to the pan and mix well in the sauce until coated well. Cook this for a few minutes.
Add cooked prawns to the pan and mix everything together to spread the prawns equally among the noodles. Cook this for a few minutes.
Remove the pan from heat and finally, garnish the tangy tomato prawn noodles with fresh coriander leaves.
Tangy tomato prawn noodles are ready to serve.