Cauliflower Galette with Roasted Tomato and Red Pepper Mornay Sauce

A flaky, savoury galette filled with roasted cauliflower and a creamy, flavour packed tomato and red pepper sauce mornay sauce.

I had this idea to make a tomato galette, but I didn’t want to go the usual route with slices of fresh tomato. They can get a little too watery for me, especially in a galette, where the crust really deserves to stay crisp. So instead, I roasted the tomatoes with red peppers and garlic, blended them into a rich purée, and turned that into a creamy mornay sauce. It’s cozy, savoury, and way more satisfying. Roasted cauliflower on top makes it feel hearty and balanced, perfect for when you want something a little special but still comforting.

What’s a Mornay Sauce?

A mornay sauce is basically a cheese sauce made from béchamel (a classic French white sauce of butter, flour, and milk). Once it’s thickened, cheese is stirred in until smooth and melty. In this version, I’ve added roasted tomato and red pepper purée for extra flavour, it’s cozy, savoury, and perfect for this galette.

Planning Ahead

You can make this entire galette in one day, but you’ll need to start early to allow time for cooling the mornay sauce and resting the dough. If you prefer a more relaxed approach, here’s a 2-day plan to break it up into manageable steps.

Galette Dough

• 155g Ap Flour

• 25g Whole wheat pastry flour

• 121 g cold butter, cubed

• 18 g melted butter (cooled)

• 47 g cold water

• 2 g salt

• 4g vinegar white or apple cider

Galette Dough Method

1. Add the flour to the bowl of a stand mixer.

2. Pour in cooled melted butter and gently toss until mixture becomes slightly crumbly. The melted butter coats the flour in fat to ensure you get a super tender and buttery crust.

3. Add cold, cubed butter.
   Using a stand mixer fitted with the paddle attachment mix on low
   leaving some larger flakes for extra flakiness.

4. Mix cold water, salt and vinegar together.

5. Drizzle the water-vinegar-salt mixture into the flour gradually,
   gently tossing and pressing the dough until it just comes together.

6. Gather the dough into a rough ball, then shape into a flat disk.

7. Wrap the disk in plastic wrap (or parchment) and refrigerate for at least 2 hours,
   or up to 2 days.

Roasted Pepper and Tomato

Note: This makes more than you need for the mornay sauce, but it freezes beautifully and adds amazing depth to soups, rice dishes, stews, or sauces. I always make a batch to keep on hand, it’s an easy way to build flavour into other meals.

• 150g red peppers

• 180g tomato

• 2 garlic cloves

• 1/2 tsp sea salt

Roasting Instructions:

1. Preheat oven to 400°F (220°C).

2. Prep the vegetables:

   • Red peppers: Cut in half or quarters if they’re large. Remove seeds and stems.

   • Tomatoes: Halve or quarter if large.

   • Garlic cloves: Remove skin

3. Arrange on a baking sheet:

   • Place everything on a parchment-lined tray.

   • Drizzle lightly with olive oil and season with salt.

4. Roast for 25–30 minutes, or until:

   • Peppers are blistered and soft.

   • Tomatoes are collapsed and slightly charred.

   • Garlic is golden and soft.

5. Cool slightly, then:

   • Using a blender or immersion blender blend until smooth. You can remove the skin of the pepper and tomato but i like the extra flavour the skin provides and in this preparation it doesn’t effect the final texture of the sauce.

   Tomato Roasted Pepper Mornay

   Ingredients:

   • 100g whole milk

   • 150g tomato and roasted red pepper purée (see roasting instructions above)

   • 25g all-purpose flour

   • 25g butter

   • 40g Gruyère cheese, grated (cheddar, Swiss, or Parmesan also work well)

   • Salt and pepper to taste

   Instructions:

1. Make the roux:
   In a saucepan, melt the butter over medium heat. Add the flour and whisk constantly for 1–2 minutes, until the mixture bubbles and smells lightly toasted.

2. Add the liquids:
   Gradually whisk in the milk and tomato-pepper purée. Keep whisking to maintain a smooth consistency.

3. Simmer and thicken:
   Cook over medium-low heat, stirring frequently, until the sauce thickens and coats the back of a spoon (about 3–5 minutes).

4. Add the cheese:
   Remove from heat and stir in the grated cheese until fully melted and incorporated.

5. Season to taste: :

   Start by adding a small pinch of salt (and/or pepper), stir, then taste the mixture. Add more if needed, a little at a time, until the flavour is well-rounded and to your liking. Remember that we will season the cauliflower as well so its best to not over salt the mornay sauce.

6. Cool:
   Cover the top of the mornay sauce with plastic wrap, make sure it touches the top of the sauce to prevent a skin from forming Let the sauce cool to room temperature then refrigerate until ready to use for the galette. Stores well in the fridge for up to 4 days or in the freezer for up to 3 months.

   

Cauliflower Prep

Ingredients:

• 270g cauliflower, cut into small florets

• 1 tbsp neutral oil (such as sunflower, canola, or light olive oil)

• ¼ to ½ tsp salt, to taste

Instructions:

1. Preheat oven to 425°F (220°C).

2. In a bowl, toss cauliflower with oil and salt.

3. Spread on a parchment-lined baking sheet in a single layer.

4. Roast for 20–25 minutes, or until tender and golden brown in spots.

5. Let cool completely before using in the galette.

Egg Wash

Ingredients:

• 1 egg

• 1 tbsp milk

Whisk together until smooth. Brush onto the crust before baking for a golden, glossy finish.

Galette Assembly and Bake

1. Roll the dough:
   On a lightly floured surface, roll out your galette dough into an 11-inch round and to about a ¼ inch thick. To tidy the shape, place an 11-inch bowl upside down on the dough and cut around it to form a clean circle.

2. Add the sauce:
   Spread a thick layer of Tomato Roasted Pepper Mornay sauce (and ⅔ over the center of the dough, leaving a 1½–2 inch border around the edges.

3. Add the cauliflower:
   Evenly distribute the roasted cauliflower florets over the sauce.

4. More mornay:
   Dot the top with a few small spoonfuls of extra mornay sauce for added creaminess.

5. Fold and finish:
   Fold the edges of the dough inward over the filling, pleating as needed to create a rustic edge. Brush the crust with the egg wash.

6. Bake:
   Bake at 400–425°F (200–220°C) for 35–45 minutes, or until the crust is golden brown and crisp.