After the success of this tart at a recent al fresco do we had with friends and neighbours, I am compelled to share its vegetarian delights with you.
There are tarts, and there are tarts, but this one is on another level, based on a recipe from leading Scottish chef Martin Wishart.
Being rich, creamy and earthy all at the same time, it has something for everyone, whether it’s a portion at a party, or a slice with a crisp green salad for supper.
The combination of sautéed potatoes and slow-cooked onions, bound together with eggs, cream and cheese is an absolute delight, and even makes a meat-eater like me forget carnivorous pleasures (for one meal anyway).
Although it has similarities with a quiche in its ingredients, that is where the similarities end.
This is a tart for grown-ups.
INGREDIENTS
shortcrust pastry (for a 30cm tart)
300g plain flour
150g cold butter, cubed
5g salt
Few tbs of cold water
Put flour, butter and salt in a food processor and pulse a few times until you have a mix like breadcrumbs. This should only take seconds.
Then add cold water a little at a time while still pulsing, until the pastry just starts to clog together.
Tip out onto a cool work surface and form into a smooth ball, without kneading too much. Flatten a little, cover with clingfilm and put in the fridge for an hour to rest.
After the pastry has rested, take out of the fridge and allow the chill to come off the pastry.
Roll out to about the depth of a pound coin, and place into a 30cm tart tin. Press into the sides, trim off the excess, prick the base with a fork, cover with cling film and rest again in the fridge (even overnight).
Pre-heat your oven to 180℃/160℃ fan and put in a large baking tray.
To blind bake the pastry case, cover the tin with crumpled baking paper and fill with baking beans or rice to weigh everything down, making sure you get down into the edges.
Place onto the hot baking tray in the oven for about 15 minutes, then remove the baking paper and beans/rice.
Brush the base of the tart with some beaten egg, to create a seal, which will keep the base crisp, even when the wet filling is added later.
Put back in the oven for another 10 minutes or so until the pastry is a nice golden colour.
Keep an eye on the pastry at this stage, since all ovens differ, and my timings are only a guide.
Melt the butter in a large frying pan, and over a medium heat, cook the onions with a pinch of salt until meltingly soft, golden and sweet.
At the start, you will think there are far too many onions, but have faith, as they will cook down into just the right amount for the base of the tart.
The slower you cook the onions, the sweeter and better they will be, as this gives them plenty of time to release their natural sugars and caramelise into a golden brown tangle. (I cooked mine for about 45 minutes).
If you feel the onions aren’t as sweet as you would like, sprinkle with a little sugar to help the caramelisation, but keep tasting as you go.
This is the most important part of the tart so give it your best shot.
When the onions are done to perfection, leave to one side to cool.
Combine the onions and potatoes (you might need to warm the onions a little to help them mix with the potatoes) and layer over the base of the cooked pastry case.
Try and get some of the potatoes to stand upright so they stick out of the surface of the tart filling, for no other reason than it looks great!
Beat the eggs with the cream and a pinch of salt, then stir through the parmesan.
Pour the egg and cream mixture over the onions and potatoes, to near the top of the tart, before putting it on the hot baking tray in the oven. With the little mixture remaining, top up the tart to as near the top as you can get it (don’t worry if there is a little egg and cream mixture left over*), and sprinkle over the grated Gruyere cheese.