Out of the four Ramen places I have been to in PGH, Zen is the only, single, solitary place I would go for ramen.
The ramen broth and toppings are far superior than the rest. The charsiu has a great balance of fat a d meat and you get 3 of them on top. The other toppings include bamboo shoots, corn, seafood cake, soft boiled egg, etc. based on the bowl you choose. There is even a curry broth version you can eat with a super crispy chicken katsu that is quite delicious.
The menu also offers decent appetizers and also choices for one of the best fried rice bowls I ever had here. The yakisoba noodle choices hit the mark if you want dry noodles!
Overall, I recommend! Check'em out!