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Mornay onion tart

In a shortcrust pastry base, a rather thick onion tart, where onions and lardons are deliciously bound with a Mornay sauce.

3,267 5.0/5 based on 27 reviews

Last modified on: June 23^th 2024

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For 12 people, you will need:

1 0 kg 2 g Shortcrust pastry (pâte brisée)
2 0 kg 8 g onion
3 ½ cup butter
4 1 ¹⁄₃ cup smoked pork belly (or thick cut streaky bacon)
5 8 tablespoons vinegar
6 0 kg 2 g Mornay Sauce
7 0 kg grated cheese

Change to the quantities for: 2 people 3 people 6 people 12 people 18 people

Change measures: Metric

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How long will it take?

Time required for this recipe:

Preparation	Cooking	Start to finish
1 hour 3 min.	1 hour 11 min.	2 hours 14 min.

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Step by step recipe

Stage 1 - 20 min.

Roll out 0 kg 2 g Shortcrust pastry (pâte brisée) then line a 22 cm (9-inch) diameter high-sided baking tin, which you will have placed on a sheet of baking paper in a baking tray.

Leave any excess dough around the edges, then place in the fridge to set aside.

Stage 2 - 10 min.

Prepare and slice 0 kg 8 g onion (a mandolin is ideal for this).
This may seem like a lot, but don't worry, they'll reduce when cooked.

Stage 3 - 3 min.

In a large saucepan over medium heat, melt ½ cup butter, and when hot, add the onions.

Season with salt and stir well.

Cover for the first 5 minutes.

Stage 4 - 10 min.

Leave to cook until the onions are tender, checking the salt seasoning as cooked onions tend to be a little sweet.

Stage 5 - 5 min.

Your onions should be fairly dry, with little or no cooking juices.
If this isn't the case, because they've given off a lot of water during cooking, drain them in a fine sieve.

Set aside.

Stage 6 - 3 min.

Preheat oven to 200°C (390°F).

Cut 1 ¹⁄₃ cup smoked pork belly (or thick cut streaky bacon) into small pieces.

Stage 7 - 8 min.

Toast them, without adding fat, in a small frying pan over medium heat.

Stage 8 - 1 min.

When toasted to your liking, add 8 tablespoons vinegar, and stir until evaporated.

Stage 9 - 2 min.

It's not essential, but I recommend adding 2 or 3 spoonfuls of already-cooked onions to the pan at the end of cooking, then stirring well to capture all the flavor of the grilled bacon.

Stage 10 - 2 min.

Pour the lardons + onions into the remaining onions and mix well.

Stage 11 - 2 min.

Add 0 kg 2 g Mornay Sauce and mix well.

Stage 12 - 20 min.

Take the pastry mould out of the fridge, cut the excess pastry around the edges of the mould, place a sheet of baking paper on the bottom and fill with ceramic balls (or similar).

Bake at 200°C (390°F) for 20 minutes.

Stage 13 - 5 min.

In the meantime, you can roll out the pastry scraps into small strips to decorate the tart.

Stage 14 - 1 min.

After 20 minutes, remove the baking tray from the oven...

Stage 15 - 5 min.

... and remove paper and beads.

Stage 16 - 2 min.

Fill the tart with the onion-lardon-Mornay mixture.

Stage 17 - 2 min.

If you have made some, place the pastry strips on top.

Stage 18 - 3 min.

Sprinkle with a little grated cheese.

Stage 19 - 30 min.

Bake for a further 30 minutes.

Stage 20

Enjoy warm or hot, on its own or with a small green salad.

Remarks

If you find your onions a little too soft at the end of cooking, you can add a good glass of dry white wine.

If you don't have a Mornay sauce, use a Béchamel sauce to which you can add grated cheese to taste.

You'll notice that in this recipe, the onions are cooked without coloring, but if you prefer, you can caramelize them. In this case, increase the weight of onions to 1.5 kg, as they will reduce even more.

Keeping

1 or 2 days in the fridge, protected by cling film.

Source

Home made.

Nutritional information

Whole recipe
Energetic value	Proteins	Carbohydrates	Fats
6,839 Kcal or 28,634 Kj	717 gr	2,988 gr	2,568 gr
342 %	276 %	282 %	389 %

Per 100 g
Energetic value	Proteins	Carbohydrates	Fats
181 Kcal or 758 Kj	19 gr	79 gr	68 gr
9 %	7 %	7 %	10 %

Per person
Energetic value	Proteins	Carbohydrates	Fats
570 Kcal or 2,386 Kj	60 gr	249 gr	214 gr
28 %	23 %	23 %	32 %

% are calculated relative to a Recommended Dietary Intake or RDI of 2000 k-calories or 8400 k-joules by day for a woman (change to a man).

Possible allergens in this recipe: Gluten, Milk, Egg, Sulfites

How much will it cost?

For 12 people : 10.74 €
Per person : 0.90 €

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Note: Be careful, these prices are only an estimate, you can consult the table of prices by ingredients used for this estimate.

This recipe uses (among others)

	Onion: You can get more informations, or check-out other recipes which use it, for example: Paella, Creamy artichokes, Chicken breasts in a potato crust, Soup Cornouaillaise, Mushroom bourguignon, ... All
	Shortcrust pastry (pâte brisée): You can get more informations, or check-out other recipes which use it, for example: Gisèle's Pasties, Mexican tart, Potimarron and Parmesan tart, Leek and Mimolette tart, Paté en croute (terrine in a pie crust), ... All
	Mornay Sauce: You can get more informations, or check-out other recipes which use it, for example: Spinach Mornay, Small green vegetables in Mornay sauce, ... All
	Smoked pork belly (or thick cut streaky bacon): You can check-out other recipes which use it, like for example: Express sauerkraut, Warm lentil salad, Boeuf (beef) bourguignon, Soup Cornouaillaise, ... All