Cut all the veggies in French fries shape. In separate bowls.

One by one fry each accordingly
Potatoes cook for 3-5 minutes till they are half way done then add zucchini until slightly soft then add eggplant and onion stir fry for 1-2 minutes add ginger/ garlic paste salt pepper and crushed pepper cook for 4-5 minutes

Serve hot as is or with boiled rice.