Irresistible Tomato Zucchini Gratin Ready in 40 Minutes

You know those summer evenings when your garden is overflowing with zucchini and tomatoes, and you need something quick, delicious, and a little bit fancy? That’s exactly how my Tomato Zucchini Gratin was born—out of necessity and a love for simple, fresh flavors. This dish has become my go-to for busy weeknights and last-minute dinner parties alike. It’s ready in under 40 minutes, but tastes like you spent hours in the kitchen. The best part? That golden, cheesy crust hiding layers of tender zucchini and juicy tomatoes. Trust me, even the pickiest eaters at your table will be asking for seconds.

Why You’ll Love This Tomato Zucchini Gratin

This dish has stolen hearts (and stomachs) for so many reasons – here’s why it’ll become your new favorite too:

• Effortless elegance: It looks fancy but takes just 10 minutes of hands-on prep. Perfect for when you need to impress but don’t have time to stress.
• Garden glory: Showcases summer’s best produce with minimal fuss – those zucchini and tomatoes really shine.
• Cheese magic: That golden, bubbly mozzarella-Parmesan crust? Absolute perfection against the tender veggies underneath.
• Versatile star: Equally at home as a vegetarian main, elegant side dish, or brunch showstopper.
• Leftover dreams: Tastes even better the next day (if it lasts that long!).

Seriously – this gratin solves the “what should I make?” dilemma all summer long.

Ingredients for Tomato Zucchini Gratin

Here’s everything you’ll need to make this summer favorite – simple ingredients that pack big flavor:

• 2 medium zucchinis (about 8 inches long), sliced into 1/4-inch rounds
• 2 large tomatoes, sliced into 1/4-inch rounds (go for firm-but-ripe ones)
• 1 cup shredded mozzarella (the whole-milk kind melts best)
• 1/4 cup grated Parmesan (the real stuff, not the green can!)
• 2 tbsp olive oil (good quality makes a difference here)
• 1 tsp dried oregano (crush it between your fingers to wake up the flavor)
• 1/2 tsp garlic powder (trust me, powder works better than fresh here)
• Salt and pepper to taste (I use about 1/2 tsp salt and 1/4 tsp pepper)

Ingredient Notes & Substitutions

Out of something? No worries! Here’s how to adapt:

• Swap dried oregano for 1 tbsp fresh oregano or basil leaves
• Use vegan cheese blends if needed – just check they melt well
• Yellow squash works beautifully instead of zucchini
• Pat veggie slices dry with paper towels to prevent a watery gratin
• For extra richness, add a sprinkle of breadcrumbs mixed with melted butter

The key is keeping those veggie slices uniform so everything cooks evenly!

How to Make Tomato Zucchini Gratin

Okay, let’s get to the fun part! Making this gratin is so simple you’ll wonder why you don’t make it every week. Here’s how it all comes together:

1. Preheat your oven to 375°F (190°C). This is crucial – you want that oven nice and hot when the gratin goes in.
2. Layer those beauties: Start with zucchini slices at the bottom of your baking dish (I use an 8×8 inch), slightly overlapping like little soldiers. Then add tomato slices in the same pattern. Repeat until you’ve used all your veggies, ending with tomatoes on top.
3. Drizzle and dust: Pour that lovely olive oil evenly over the top, then sprinkle with oregano, garlic powder, salt, and pepper. I like to use my fingers to make sure the spices are evenly distributed.
4. Cheese blanket: Now the good stuff! Sprinkle mozzarella first, then Parmesan over the top – this creates the perfect crust.
5. Bake to perfection: Pop it in the oven for 25-30 minutes. You’ll know it’s ready when the cheese turns that magical golden brown and starts bubbling at the edges.
6. Rest and serve: Let it sit for 5 minutes (so hard to wait, I know!) – this helps it set so you get perfect slices.

Pro Tips for Perfect Tomato Zucchini Gratin

After making this dozens of times, here’s what I’ve learned:

• Dry those veggies: Pat slices with paper towels – watery vegetables make a soggy gratin.
• Watch your bake time: Ovens vary – start checking at 20 minutes if yours runs hot.
• Broiler finish: For extra browning, hit it with the broiler for last 1-2 minutes (but don’t walk away!).
• Let it rest: Those 5 minutes make all the difference for clean slices.

Serving Suggestions for Tomato Zucchini Gratin

This gratin plays so nicely with others! My favorite way to serve it is alongside garlic-rubbed grilled chicken – the flavors complement each other perfectly. For a meatless meal, pair it with crusty bread to soak up all those delicious juices and a simple arugula salad with lemon dressing. It’s also fabulous with grilled fish or as part of a brunch spread with poached eggs on top. Honestly? Sometimes I just eat it straight from the baking dish with a fork – no judgment here!

Storing and Reheating Tomato Zucchini Gratin

Here’s the good news – leftovers taste even better! Store cooled gratin in an airtight container in the fridge for up to 3 days. When reheating, skip the microwave (it makes the veggies soggy) and pop it back in a 350°F oven for about 10 minutes instead. That crispy cheese crust comes right back to life! If you’re feeling fancy, sprinkle a little fresh Parmesan on top before reheating for extra flavor.

Tomato Zucchini Gratin Nutrition

Let’s be real – we’re eating this because it’s delicious, but bonus: it’s actually good for you too! Nutrition varies based on your exact ingredients, but per serving you’re looking at about 180 calories, 12g fat (the good kind from olive oil and cheese!), and a solid 3g fiber from all those gorgeous veggies. Not too shabby for something that tastes this indulgent!

FAQs About Tomato Zucchini Gratin

You’ve got questions? I’ve got answers! Here are the ones I get asked most about this beloved dish:

Can I use yellow squash instead of zucchini?
Absolutely! Yellow squash works beautifully in this gratin. Just make sure to slice it to the same thickness as the zucchini (about 1/4-inch) so everything cooks evenly. The flavor is nearly identical – just a bit sweeter. You could even do half zucchini, half yellow squash for a pretty color contrast!

Can I prep the gratin ahead of time?
You bet! Assemble everything (except the cheese) up to 12 hours in advance – just cover and refrigerate. When ready to bake, let it sit at room temp for 20 minutes, add the cheese, and pop it in the oven. Might need an extra 5 minutes baking time since it’s cold.

Is this gratin freezer-friendly?
Honestly? Not really. The texture gets watery when thawed. But here’s a trick – bake individual portions in ramekins, then freeze those. Reheat from frozen at 375°F for about 20 minutes. Not quite as perfect as fresh, but still tasty in a pinch!

Share Your Tomato Zucchini Gratin Experience

Now I want to hear from you! Did your family go crazy for this gratin like mine does? Snap a photo and tag me – I live for those cheesy, golden-brown masterpieces. Leave a comment below with your favorite twist or who you shared it with. Happy baking, friends!

Irresistible Tomato Zucchini Gratin Ready in 40 Minutes

• Author: Judy Wilson
• Prep Time: 10 mins
• Cook Time: 25 mins
• Total Time: 35 mins
• Yield: 4 servings 1x
• Category: Side Dish
• Method: Baked
• Cuisine: Mediterranean
• Diet: Vegetarian

Print Recipe

Pin Recipe

---

Description

A delicious and healthy dish combining zucchini and tomatoes with a cheesy crust. Perfect for a light lunch or side dish.

---

Ingredients

Scale 1x2x3x

• 2 medium zucchinis, sliced
• 2 large tomatoes, sliced
• 1 cup shredded mozzarella cheese
• 1/4 cup grated Parmesan cheese
• 2 tbsp olive oil
• 1 tsp dried oregano
• 1/2 tsp garlic powder
• Salt and pepper to taste

---

Instructions

1. Preheat oven to 375°F (190°C).
2. Layer zucchini and tomato slices in a baking dish.
3. Drizzle with olive oil and sprinkle with oregano, garlic powder, salt, and pepper.
4. Top with mozzarella and Parmesan cheese.
5. Bake for 25-30 minutes until cheese is golden and bubbly.
6. Let rest for 5 minutes before serving.

---

Notes

• Use fresh zucchini and tomatoes for best results.
• Add fresh basil for extra flavor.
• Serve warm.

---

Nutrition

• Serving Size: 1 serving
• Calories: 180
• Sugar: 5g
• Sodium: 220mg
• Fat: 12g
• Saturated Fat: 4g
• Unsaturated Fat: 7g
• Trans Fat: 0g
• Carbohydrates: 10g
• Fiber: 3g
• Protein: 9g
• Cholesterol: 15mg

Keywords: tomato zucchini gratin, vegetarian side dish, baked vegetables