Set a large baking sheet in the oven, then preheat oven to 375 degrees F (190 C) (with pan inside). Meanwhile, combine ricotta, parmesan, salt, and pepper in a small bowl. Chop all veggies to similar bite sizes.
On a floured surface, roll dough into roughly a 15 inch wide circle. Transfer dough to parchment paper, then spread on the ricotta mixture, leaving about 2 inches along the outside. Arrange veggies on top of ricotta (hint: arrange them in a circle so if you want everyone to get the same amount of each veggie, or arrange in lines if you want people to pick and choose the slices they like best.) Fold the dough left on the border over the veggies to form a crust.
Drizzle oil over veggies and brush crust with egg. Slide the parchment paper with the tart onto the hot baking sheet* and bake for 25 to 30 minutes, or until crust is golden brown.
*This will help to ensure the bottoms cooks through without having to "blind bake" it!