Easy Upside Down-Puff Pastry Croque Monsieur Tart
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Joining Cindy and Mary Ann since it’s Sunday…and wishing they could come for lunch! This easy upside-down puff pastry Croque Monsieur tart is so delicious! Perfect with a salad for lunch on the porch!
What is an upside-down puff pastry tart?
In the last few weeks, you may have noticed this viral trend on Instagram or TikTok. An upside-down puff pastry square tart can be sweet or savory. The result is a sort of rustic elegance. Puff pastry is the main ingredient and is something I keep a box of in the freezer.
So when I first saw it @lilygbakes, I grabbed my box from the freezer, thawed it, and made a similar recipe as her onion tarts. It always takes me a few tries to get it right. A few days and a couple of boxes of puff pastry later, I came up with a savory ham and cheese upside-down tart based on the ingredients of the traditional French sandwich.
The Ingredients You Will Need to Make this Easy Upside-Down Puff Pastry Tart
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- Extra virgin olive oil
- Puff Pastry
- Gruyère cheese
- Dijon mustard
- Béchamel sauce
Why do we call it a Croque Monsieur?
A Croque Monsieur is basically an extravagant ham sandwich in French. It’s comprised of French ham, which we found in the deli department at Whole Foods. It was called Jambon Royale. We asked for thin slices.
Next, you’ll need a French cheese like Gruyère and a few condiments. Dijon mustard and a Béchamel sauce are a must.
Leave it to the French to come up with something so simple but delicious with so much flavor. Add an egg, and it’s a Croque Madame. Making it using puff pastry replaces white bread, but basically, the rest of the ingredients are that of a traditional Croque Monsieur.
Make a Béchamel Sauce
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I’ll take any excuse to use my mini copper pots! I wanted to make only a small amount of Béchamel sauce. Just enough for four tarts. I used equal parts butter and flour, about a tablespoon of each. I melted the butter in one small pot over low heat. Added the flour and whisked while adding the warmed milk slowly until I had the right sauce consistency.
Assembling the Upside-Down Puff Pastry Croque Monsieur Tarts
Step-by-Step Assembly
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- Line a baking sheet with parchment paper and then drizzle olive oil in 4 rectangles or squares separated enough that they will be spaced out when you start building your tarts.
- Layer a thin piece of ham over the olive oil on the parchment paper, folding it over to keep it shaped like the puff pastry you will eventually use to cover it.
- Spread a little béchamel sauce on top of each slice of ham, and then a spread of Dijon mustard.
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4. Top with slices of Gruyére cheese.
5. Top with the puff pastry, pressing down all the way around, then brush each pastry with an egg wash.
6. Sprinkle with a little flaky sea salt and bake.
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7. Flip them over and place them on a cooling rack.
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Easy Upside Down-Puff Pastry Croque Monsieur Tart
An upside-down tart using puff pastry to make a delicious Crogue Monsieur.
Ingredients
- 4 Slices French ham, sliced thin
- Extra virgin olive oil
- 8 small slices of Gruyère Cheese
- 1 tablespoon Dijon Mustard
- 1 Tablespoon Béchamel Sauce
- 1 sheet puff pastry
Instructions
- Preheat oven to 350º
- Line a large baking sheet with parchment
- Drizzle olive oil in 4 rectangles on the parchment
- Top with the ham, Béchamel sauce, mustard, and Gruyère cheese
- Then place a sheet of puff pastry over the top and press on all four sides.
- Pierce with a fork and brush with an egg wash, sprinkle flaky sea salt and bake for 15 minutes.
- Remove from the oven and flip onto a cooling rack.
- Serve warm!
Can I use Phyllo dough instead of puff pastry?
I would say no. There is a difference in ingredients and how they are made. Phyllo dough is paper thin and made using oil. Puff pastry is made using butter. So it is not recommended to substitute one for the other when making a recipe.
Pin for later
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What can you do with the leftover puff pastry scraps?
My friend Sheri has the best ideas. This post-making dough scrap treats instantly reminded me of my childhood. My mom always used leftover homemade pie dough to make cinnamon sugar treats we devoured. Sheri suggests using them dipped in chocolate or Nutella or sprinkled over ice cream. You can read Sheri’s post here.
A Few More Sunday Favorites:
Pretty Floral Plates Perfect for Upside-Down Tarts
Did you see my post last week where I shared my simple Mother’s Day table? These plates are perfect for serving upside-down tarts, salads, or desserts! They add a lovely touch to any table. Even just one with a plate of cookies. They are so lovely!
Studio Spelling
Rachel Spelling makes art using paint chip cards. I saw this one using a Farrow & Ball paint chip card. For this collaboration, she painted ten tiny originals on the red and blue sections of the color card. Click over to @studiospelling to see more paint chip art!
Serena & Lily Living Room Sale
Serena & Lily has a 25% OFF SALE on living room essentials. A few new pieces caught my eye, including the chair I’ve loved since working at Serena & Lily Westport store. I recently visited their newest store in Roslyn, New York. Read more here.
I’ve been dying to try this trend! Yours looks easy and delicious, and I love that you did a savory version – there are so many sweet ones out there! Thank you for including my dough scraps tip too! xo
Those dough scraps sound as good as churros!
OMG I can ‘t imagine anything more delicious or dangerous than that delicious tart!! Serena and Lily living room sale sounds fabulous as well!
Recently went to a little restaurant in La Quinta ca and had a sandwich with French ham.
Best ham I ever tasted and I thought at the time where am I going to find this delicious ham!
Thanks to you, now I know…on my way to Whole Foods to pick up some puff pastry, Gruyère cheese and….Jambon Royale! Thank you so much!
Hi Karen! You’ll have to keep me posted! I had never tried it before…It’s like I was in France! Although La Quinta sounds lovely too!
My mouth is watering, Annie! Pinned this.
Thank you Mary Ann! I wish you could stop by for lunch! xx
I’ve not tried it, most of the tarts I saw people making were fruit and I am not a fan of that. This looks delicious!
I was thinking of trying an apple, but savory tarts are my favorite!
Oh my. I must make this. My husband would adore it. Thanks.
Sandra! You’ve probably seen these trending! I tried a few, but this ham & gruyere is so good!
xx
Annie!! I’ve been dying to try this – you make it look so easy and delish and had no idea Jambon Royal was a good french ham. You always have the best ideas. xoxo
Nancy! I don’t usually like ham…unless I’m in France, but it was so good! Especially in puff pastry! haha xx