Start cooking the penne in a large saucepan of boiling water.
Heat the oil in a large frying pan.
Add the onion and cook for 3 minutes over medium heat until lightly golden, then add the garlic and cook for 1 minute more.
Add the capsicum and zucchini to the pan and cook, stirring regularly, for 2 minutes or until they begin to soften.
Add the eggplant and stir to combine.
Add the tomatoes to the pan, bring to the boil and reduce the heat to low.
Simmer, covered, for 15 minutes, stirring occasionally, until the vegetables are soft.
Uncover and cook, stirring frequently, for a further 5 minutes or until thickened slightly.
Stir in the parsley and capers and season to taste.
When the pasta is al dente, drain and serve tossed through the ratatouille.
HINT: This vegetarian dish does not include a meat substitute. If you follow a vegetarian lifestyle, make sure that other meals in the week include meat alternatives, such as legumes, tofu or soy products