Introduction

This assorted tomato tart is a simple, rustic bake that tastes like peak summer—juicy tomatoes, fragrant basil, and a crisp crust that holds everything together. The secret ingredient here is mustard. Instead of a heavy filling, you spread a thin layer of mustard directly on the crust. It adds a gentle tang, deepens the tomato flavor, and helps create a barrier that protects the crust from getting soggy.

Because the ingredient list is short, each one matters. Using a mix of tomatoes (different colors and sizes) makes the tart look vibrant and also improves the flavor balance—sweet, tangy, and slightly earthy all at once. Olive oil brings richness and helps the tomatoes caramelize slightly in the oven. After baking, the tart is finished with fresh basil leaves and fleur de sel, giving you that bright, fresh aroma and a clean salty crunch.

This tart is ideal for gatherings because it’s easy to slice and serve, and it feels special without being complicated. It works as an appetizer, a side dish, or a light lunch with a salad. And since it’s not loaded with cheese or custard, it stays fresh-tasting and not too heavy—exactly what you want when tomatoes are in season.

Why You’ll Love This Recipe

• Simple ingredients, big flavor: Tomatoes + mustard + olive oil + basil create a bold, clean taste.
• Looks impressive with minimal work: The colorful tomato pattern does the “wow” factor for you.
• Crisp crust with a smart trick: Mustard acts like a flavor base and helps prevent a soggy bottom.
• Flexible and seasonal: Use any variety of tomatoes you have and adjust the herbs to match.

Equipment

• 9-in (23 cm) tart pan (or pie dish)
• Baking sheet (to place under tart pan for stability)
• Cutting board
• Sharp knife (or serrated knife for softer tomatoes)
• Small bowl (optional, for seasoning/draining tomatoes)
• Paper towels or clean kitchen towel
• Measuring spoons and cups
• Pastry brush or spoon (for mustard and olive oil)
• Cooling rack

Ingredients

Main Ingredients

• One 9-in (23 cm) pie crust (store-bought or homemade)
• 3 tbsp mustard
• 5 assorted tomatoes (mix sizes/colors if possible)
• 1/4 cup (60 mL) olive oil
• 1 handful basil leaves
• Fleur de sel sea salt (to finish)

Optional Ingredients

• Black pepper (highly recommended)
• Garlic (1 small clove, grated or very finely minced)
• Dijon + whole-grain mustard blend (for more texture)
• A pinch of dried oregano or thyme (for a Mediterranean note)
• A little grated hard cheese (Parmesan) to help absorb moisture
• Thinly sliced onion or shallot (adds sweetness when baked)

Instructions

Step 1: Preparation

1. Preheat the oven to 350°F (180°C).

2. Place your tart pan on a baking sheet. This makes it easier to move in and out of the oven and catches any drips.

3. Fit the 9-inch pie crust into the tart pan and press it gently into the edges. Trim any excess dough if needed.

4. Optional but helpful: lightly dock (prick) the bottom of the crust with a fork. This reduces puffing and helps the base bake evenly.

Tomato prep for a crisp tart

Tomatoes carry a lot of water, and that water can soften your crust if it releases too quickly. A small prep step makes a big difference:

1. Slice the tomatoes into rounds (about 1/4-inch / 6 mm thick).

2. Lay slices on paper towels and pat the tops dry.

3. If tomatoes are very juicy, let them sit for 5–10 minutes, then pat again.

This doesn’t remove flavor—it simply removes excess surface moisture so the tart bakes up cleaner and crispier.

Step 2: Mixing / Assembling

1. Spread 3 tbsp mustard in a thin, even layer over the base of the crust.

   • Keep it mostly in the center, but you can go close to the edges.

   • The goal is a thin coat—enough for flavor and a moisture barrier, not so much that it overpowers the tomatoes.

2. Arrange tomato slices on top of the mustard. You can overlap them slightly like shingles or create a pattern with different colors.

3. Drizzle 1/4 cup (60 mL) olive oil over the tomatoes. Try to cover the surface evenly so the tomatoes roast gently and the top doesn’t dry out.

4. Season lightly with fleur de sel (go easy for now—you’ll add more at the end). Add black pepper if using.

Step 3: Cooking / Baking

1. Bake at 350°F (180°C) for 30 minutes.

2. Visual doneness cues:

   • The crust edges should look set and lightly golden.

   • Tomatoes should look softened and slightly roasted, not raw and watery.

   • Olive oil will be shimmering on top, and the tart will smell deeply tomato-y and savory.

Optional finishing step for extra crispness

If you like a darker, crisper crust:

• Bake an extra 5–8 minutes, watching closely so the edges don’t over-brown.

• If the crust browns faster than the tomatoes, cover the edges loosely with foil and keep baking.

Step 4: Resting / Finishing

1. Remove the tart from the oven and let it rest for 10 minutes.

   • This rest is important: hot tomatoes release steam, and resting helps the moisture settle so slices hold their shape when cut.

2. Scatter fresh basil leaves over the top. Tear them for a more aromatic finish.

3. Finish with a final sprinkle of fleur de sel right before serving for a clean, crunchy salt pop.

Tips & Notes

• Mustard choice matters: Dijon gives classic sharpness; whole-grain adds texture; a mild mustard keeps the tart gentle. Use what matches your audience.
• Keep the mustard layer thin: A thick layer can dominate the tomato flavor. Think “painted on,” not “piled on.”
• Dry the tomatoes: This is the easiest way to avoid a watery tart and soft crust.
• Slice thickness: Too thin and tomatoes melt into sauce; too thick and they stay raw. Aim for about 1/4 inch.
• Cutting tip: Use a very sharp knife and slice gently. A serrated knife can help if tomatoes are very soft after baking.
• Flavor upgrade without extra work: Add a pinch of black pepper and a few drops of olive oil after baking—fresh oil tastes brighter than baked oil.

Variations

Ingredient Variations

• Herb swap: Replace basil with fresh thyme leaves or oregano after baking.
• Garlic layer: Mix a little grated garlic into the mustard before spreading for a deeper savory backbone.
• Cheese assist: Sprinkle a very thin layer of grated Parmesan on the crust before the mustard. It helps absorb moisture and adds umami.
• Onion base: Add very thin onion or shallot slices under the tomatoes for a sweet-savory note.
• Spice kick: Add chili flakes before baking for gentle heat.

Protein Alternatives

This tart is naturally vegetable-forward. If you want a more filling version:
• Add thin slices of prosciutto after baking (so it stays silky, not dried out).
• Add flaked tuna or anchovy touches for a bold Mediterranean style (use lightly).

Dietary Variations

• Vegetarian: This recipe is vegetarian as written.
• Gluten-free: Use a gluten-free crust. Bake time may vary, so watch for edge browning and firmness.
• Dairy-free: Naturally dairy-free if your crust contains no butter (use a dairy-free crust if needed).

Storage & Make-Ahead

• How to store leftovers: Cool completely, then cover and refrigerate.
• Refrigerator duration: Best within 2–3 days.
• Freezer instructions: Freezing is possible, but tomatoes can become watery after thawing. If you freeze, wrap slices tightly and reheat in the oven to re-crisp the crust.
• Make-ahead preparation tips:

• Slice and dry the tomatoes up to a few hours ahead, then store them in the fridge on paper towels.

• Assemble right before baking for the crispest result.

Serving Suggestions

• Serve with a simple green salad (lemon vinaigrette pairs beautifully with mustard and tomatoes).
• Add olives and cucumbers for a light Mediterranean plate.
• Pair with soup (vegetable soup or tomato soup makes it feel like a complete meal).
• For brunch, serve with soft eggs on the side.
• Refreshing drink pairing: sparkling water with lemon, iced tea, or a crisp white wine.

Time Breakdown

• Preparation Time: 20 mins
• Cooking Time: 30 mins
• Baking time: 30 mins
• Chilling Time: —
• Rising Time: —
• Marinating Time: —
• Total Time: 50 mins

Servings : 8

Nutritional Information (Per Serving)

(Estimated; depends on crust type and tomato size.)
• Calories: ~240 kcal
• Protein: ~3 g
• Carbohydrates: ~18 g
• Fat: ~18 g
• Sodium: varies (mustard + salt level)

Frequently Asked Questions

Can I use leftovers or substitutions?
Yes. Any tomato variety works—just aim for a mix of color and size if possible. If you don’t have fleur de sel, use a small pinch of flaky salt. Mustard can be Dijon, mild, or whole-grain depending on taste.

Can I make this recipe ahead of time?
You can bake it earlier the same day and serve at room temperature. For the best basil aroma, add basil right before serving. If you want it warm, reheat briefly in the oven.

How do I reheat it properly?
Reheat on a baking sheet at 350°F (180°C) for 8–12 minutes until warmed through and the crust crisps again. Avoid microwaving if you want a crisp base.

Can I freeze this recipe?
You can, but tomatoes may release extra moisture after thawing. If freezing, reheat in the oven until hot and slightly crisp; it won’t be quite as fresh as day one, but still tasty.

Conclusion

This assorted tomato tart is proof that a short ingredient list can still deliver something elegant and satisfying. The mustard base adds depth, olive oil carries the tomato flavor, and basil + fleur de sel bring the freshness right at the end. Bake it when tomatoes are at their best, slice it for sharing, and enjoy a simple tart that feels bright, classic, and effortlessly special.