Mini Croque Monsieurs

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These easy mini croque monsieurs are bite-size appetizer versions of the classic French sandwich made with flaky puff pastry, creamy béchamel, ham, and nutty gruyère! 

If there is one thing I always have stashed in my freezer, it is puff pastry. I think it’s such a freezer staple because there is so much you can do with it! It’s perfect for whipping up everything from savory dinners to sweet treats, and even quick snacks.

This time, I was inspired to create fun little hors d’oeuvres, featuring the classic flavors of a French croque monsieur sandwich in appetizer portions. If you’re not familiar, a croque monsieurs are basically ham and cheese sandwiches taken to the next level.

The exact origins of the croque (“crunch” or “munch”) monsieur (“gentleman”) are unclear, but it’s a sandwich of toasted bread slices with ham and slices of cheese, covered in rich bechamel cheese sauce and nutty Gruyère cheese or another Swiss cheese, and broiled to melty golden brown perfection.

In Paris, the béchamel sauce is reportedly an optional component, and presentation varies from one brasserie to another. Here in Montreal, I often see it served as an open-faced sandwich. A croque madame is a croque monsieur with a fried egg on top!

In any case, it is delicious, and these mini croque monsieurs have all the flavor in a bite-size format. This mini version is easy to prepare and makes for the perfect party appetizer, or a quick, satisfying snack.

Why You’ll Love these Mini Croque Monsieurs

They’re so easy to make. With just a few ingredients and minimal prep time, these little bites of heaven are surprisingly simple to make, so anyone can make them.

They’re ideal for any occasion. Whether you’re hosting a party, needing a quick snack, or looking for a light lunch option, these mini croque monsieurs fit the bill.

It is the ultimate comfort food. The combination of crispy puff pastry, melted Gruyere cheese, and savory ham hits all the right notes for comfort food and a perfect appetizer.

Ingredient Notes

Puff Pastry

Puff pastry is my choice for a flaky, buttery little cup to hold all that melty goodness. I always buy an all-butter frozen puff pastry as I find it has by far the best flavor, but any puff pastry will work. Phyllo is another good option if you prefer it.

Dijon Mustard

This adds a nice tangy flavor that complements the savory ham and nutty cheese. I just brush a little inside the puff pastry cups before filling them. If you’re not a fan, you could go lighter on it, or skip it, but it really adds to the overall flavor.

Butter

Butter forms the base of the béchamel sauce (the roux). It adds to rich and creamy flavor of the bechamel. I prefer to use unsalted butter.

Onion

I like to sauté some finely chopped onion in the base of the béchamel as it adds a subtle sweetness and depth to the béchamel sauce. Shallots are a good alternative.

Flour

Flour works with butter to create the roux base, which thickens the béchamel sauce. It’s essential for achieving the right sauce consistency.

Milk

Milk is the liquid base and makes the béchamel sauce creamy. Whole milk is best for richness, but 2% works if you’re looking for a lighter option.

Ham

Of course you need some ham to make these mini croque monsieurs. I have made these with both cubes of leftover ham and sliced good quality deli ham, and both work well. When I use deli ham, I like to buy a “shaved” (very thinly sliced) ham.

If you don’t eat ham, turkey can be used instead.

Cheese

Gruyère cheese is the traditional croque monsieur cheese, but these are also great with any other swiss cheese like Emmentaler. If you prefer, you can use cheddar or any cheese you like.

Step by Step Instructions

1. Start by heating your oven to 375F. Give a 24-cup non stick mini muffin tin a good coating of oil or cooking spray to prevent sticking.

1. Take your thawed puff pastry sheet and roll it out until it’s a 10×15 inch rectangle (my puff pastry sheets start out as a 10×10 square). Cut this into 24 squares, each measuring about 2.5 inches. Place each square into a muffin cup, gently pressing them in to fit.

1. With a pastry brush, spread a thin layer of Dijon mustard inside each puff pastry cup. Pop the tin in the fridge to keep cool while you whip up the béchamel sauce.

1. In a small saucepan, melt butter over a medium heat. Add the onion and let it cook until it’s nice and soft, which should take about 2-3 minutes.

1. Add the flour, and cook, whisking constantly, for about a minute.

1. Gradually pour in the milk, continuing to whisk. Keep at it until the sauce starts to bubble up and gets thick, around 3-4 minutes.

1. Take the sauce off the heat, and add some nutmeg along with a pinch of kosher salt and black pepper to taste, whisking them in. Let the sauce cool a little.

1. Next, evenly distribute the ham into each puff pastry cup. Spoon about a teaspoon of your béchamel sauce on top of the ham and finish off with a sprinkle of cheese.

1. Put the muffin tin into your hot oven and let them bake for about 20-22 minutes. It’s done when the cheese melts and gets a nice golden brown color and the puff pastry becomes golden colored.

1. Finish by topping each mini croque monsieur with a bit of fresh thyme. Give them a little time to cool, about 5-10 minutes, and then they’re ready to enjoy!

Tips to Make the Perfect Béchamel

If you’re intimidated by French sauces, don’t be! Béchamel, a simple white sauce, is especially easy to make. Here are some tips if this is your first time making it.

• Melt the butter over medium heat to avoid browning. You want it to become just foamy enough to mix well with the flour without imparting a toasted flavor.
• After adding the flour to the butter, whisk constantly to prevent lumps from forming and ensure a smooth roux.
• Before adding any milk, cook the butter and flour mixture for about a minute to make sure your sauce doesn’t have a floury taste.
• Gently heating your milk before adding it to the roux base can prevent the shock of mixing hot and cold, which might cause clumps. I haven’t found this to be necessary personally, but it certainly never hurts.

The main thing is to whisk constantly. This is crucial for a smooth and creamy lump-free sauce. I added a bit of minced onion to mine for extra flavor, and a pinch of nutmeg.

Storage and Reheating Instructions

Let the mini croque monsieurs to cool completely at room temperature. This prevents condensation inside the storage container, which can make the puff pastry soggy.

These will also freeze very well for up to 3 months.

Reheat in an oven preheated to 350°F for about 5-10 minutes, or until they’re thoroughly warmed and the pastry has crisped back up. Avoid using the microwave, as it tends to make the pastry soft.

More Appetizers to Try

Mushroom Tart

Potato Bites

Halloumi Fries

Note: This post, originally published in 2018 has undergone significant revisions, including the recipe itself, which was originally for a croque monsieur sandwich.