Oven Roasted Ratatouille Recipe

Ingredients

• 170 g (1 yellow onion)yellow onion, thinly sliced
• 450 g (1 eggplant; about 1 lb)eggplant, thinly sliced
• 227 g (1 zucchini; about 1/2 lb)zucchini, thinly sliced
• 227 g (1 yellow squash; about 1/2 lb)yellow squash, thinly sliced
• 360 g (3 Roma tomatoes)Roma tomatoes, thinly sliced
• 240 ml (1 cup)marinara sauce
• 15 ml (1 Tbsp)olive oil
• 2.5 ml (1/2 tsp)dried basil
• 2.5 ml (1/2 tsp)dried oregano
• 0.6 ml (1/8 tsp)freshly cracked black pepper
• 0.6 ml (1/8 tsp)salt
• about 110 g (1 cup)shredded mozzarella cheese
• 15 ml (1 Tbsp), optionalfresh parsley, chopped

Instructions

1. 1

   Preheat and prepare

   Gather the ingredients and preheat the oven to 200°C (400°F).

2. 2

   Slice vegetables

   Thinly slice the onion. Cut the eggplant, zucchini, yellow squash and tomatoes into slices about 3 mm (1/8 inch) thick. Halve any slices with a larger diameter so they are easier to layer evenly.

3. 3

   Add sauce and onion

   Pour the marinara sauce into the bottom of a large casserole dish, then scatter the sliced onion evenly over it.

4. 4

   Arrange the vegetables

   Stand the eggplant, zucchini, yellow squash and tomato slices in the dish in an alternating pattern, continuing until all the slices are arranged.

5. 5

   Season and oil

   Drizzle the olive oil over the vegetables. Sprinkle the dried basil, oregano, salt and freshly cracked black pepper evenly across the top.

6. 6

   Roast the vegetables

   Put the dish in the preheated oven and roast for 40 minutes, until the vegetables have softened and the flavours have melded.

7. 7

   Add the mozzarella

   Take the dish out of the oven and scatter the shredded mozzarella over the vegetables. Return it to the oven for a further 5 minutes, until the cheese is melted and creamy.

8. 8

   Garnish and serve

   Scatter the chopped parsley over the ratatouille after roasting. Serve hot as a main or side dish.

What is ratatouille?

Ratatouille is a French vegetable dish associated with Provence, traditionally made by cooking summer vegetables with herbs. This version layers sliced vegetables over marinara and bakes them together, rather than simmering them on the hob.

Marinara and mozzarella give this take an Italian-influenced finish, while the alternating slices make the different vegetables easy to serve together.

Nutrition and macros by portion

The nutrition label shows one serving as written: 111 calories, 5g protein, 15g carbs, 6g fat.

The vegetables and marinara provide most of the carbohydrates, while the olive oil and mozzarella contribute most of the fat; the mozzarella also supplies much of the protein. To make a more balanced plate, serve a portion with a protein-rich accompaniment and a fresh salad.

Why these ingredients work

Vegetables: Eggplant, zucchini, yellow squash and tomatoes soften as they roast, each bringing a different texture and flavour. Roma tomatoes are a handy choice because their slices hold their shape for layering.

Base and topping: Marinara sits beneath the vegetables and adds a savoury sauce, while mozzarella melts over the top near the end. Dried basil and oregano season the vegetables without adding extra preparation.

Getting the slices right

Even slices: Aim for pieces about 3 mm thick so the vegetables cook at a similar pace. A sharp knife helps, and larger slices can be halved as directed.

Neat layers: Alternate the vegetables and stand them upright in the dish. They do not need to look perfectly uniform, but keeping the slices close together helps them stay arranged.

Roasting and doneness

First roast: Give the vegetables the full 40 minutes before adding the cheese. They should be softening and releasing their flavours into the marinara.

Cheese finish: Add the mozzarella for the final 5 minutes, just long enough for it to melt. The recipe does not call for browning the topping, so take the dish out once the cheese is creamy.

Serving ideas

As a main: Serve a generous portion on its own or alongside bread to catch the marinara. A simple green salad makes a fresh contrast to the soft, saucy vegetables.

As a side: Pair the ratatouille with a straightforward protein or another part of a larger meal. Add the parsley just before serving for a fresh finish.

Planning the timing

The stated total time is 65 minutes, including preparation and baking. The oven portion is 45 minutes: 40 minutes for the vegetables, followed by 5 minutes with the mozzarella.

Slice and arrange the vegetables before the dish goes into the oven. That keeps the two roasting stages simple and makes it easy to add the cheese at the right point.

Recipe notes & tips

• Slice the vegetables to a similar thickness so they soften at roughly the same rate.
• Use a large casserole dish that lets you arrange the slices upright without crushing them.
• Halve wider slices to make the alternating pattern easier to build.
• Spread the marinara and onion evenly over the base before adding the vegetables.
• Add the mozzarella only for the final 5 minutes so it melts without spending the full roast in the oven.
• Scatter the parsley over the dish just before serving.

Variations

• Add garlic: Stir finely chopped garlic into the marinara before spreading it in the dish.
• Use fresh herbs: Add chopped fresh basil or oregano as a finishing touch.
• Change the cheese: Replace the mozzarella with another melting cheese you enjoy.
• Make it dairy-free: Leave off the mozzarella for a vegetable-only version.
• Add chilli: Sprinkle chilli flakes over the vegetables with the dried herbs.
• Serve with grains: Spoon the ratatouille over cooked rice or another grain for a heartier meal.

Common mistakes to avoid

• Uneven slices: Thick pieces may stay firmer than thin ones; aim for slices about 3 mm thick.
• Overfilled dish: Crowded slices can be difficult to arrange; use a large casserole dish and keep the layers upright.
• Skipping the onion layer: The onion belongs over the marinara, where it can cook beneath the vegetables.
• Adding cheese too soon: Mozzarella can spend too long in the oven; add it after the initial 40-minute roast.
• Expecting crisp vegetables: This recipe roasts the slices until tender; do not judge doneness by whether they remain firm.
• Leaving off seasoning: Distribute the dried herbs, salt and pepper over the arranged vegetables before roasting.

How to store

Cool leftovers and store them covered in the fridge for up to 3 days. Reheat in an ovenproof dish until hot throughout, or microwave individual portions; the vegetables will be softer after storage.

Frequently asked questions