Among the many veggie restaurants located in Miraflores, El Vegetariano is one of the best choices, not only regarding flavors and quality, but also thinking of your budget. Here you can have a complete and top-quality three-course veggie lunch (entreé, main course, and dessert) plus herbal beverage, for as little as S/. 11 soles (US $4.50). 
Front Window — Photo courtesy of Isabel Guerra
The place is rather small, since it used to be a private home that's been adapted to a restaurant. So it can get really packed, especially around 1 pm, when the people who work at nearby offices come here to have lunch. 
Full house! — Photo courtesy of Isabel Guerra
But even if you have to wait a little for a table, the rewards are certainly worth it. Servings are generous, the food is excellent, and adding to this, a small serving of natural yogurt is included: take note that this is home-made yogurt, made by the restaurant staff. And you will find some jars with syrup and honey on the table, in case you prefer to pour some onto your yogurt. 
Avocado Salad, Yogurt, Maca Pudding and herbal beverage. — Photo courtesy of Isabel Guerra
You might say this is a lacto-ovo-vegetarian restaurant, since you can also find foods that include eggs, like some omelettes. But all animal meats have been replaced by soy meats, which are so well prepared and seasoned that are soft, tasty and perfect to satisfy your appetite. 
Omelette — Photo courtesy of Isabel Guerra
In conclusion: nice place, great food and really excellent prices. Even if you are not a true veggie, you will enjoy having lunch here. 