As a kid, my favourite part of Valentine's Day wasn't the candy, it was the cards. In elementary school we made little cardboard mailboxes to hang on our desks, and in the morning we would walk from desk to desk distributing our Valentines to our classmates.

So no one was left out, children were expected to have cards for every single one of the other students (this was Canada, after all). But of course you could pick your best cards for your best friends...and secret crushes.

My crush this year is not so secret (it's my perpetual Valentine, husband Sam! More on how we met, here), but he definitely will be getting my very best love letters—these edible, flaky, jam-filled beauties from canton Solothurn.

These pastries grace the cover and lend their name to the book Solothurner Liebesbriefe - Gebäck im Jahreslauf  (Love letters from Solothurn — baking throughout the year) by Elisabeth Pfluger, a prominent educator and Mundart writer from the canton of Solothurn. The book is filled with great recipes, as well as stories and poems (like this enthusiastic love poem below), all written out in dialect.

Although I have also seen them made with regular puff pastry, Pfluger's recipe suggests a rich quark dough, which turned out quite well.

Her version is filled with fruit or jam, but I also successfully experimented with blobs of Nutella, ovo spread, almond butter, and quark. I've even made them in savoury before (Cheesy Love Letters here).

For the dough:

200 g flour

1 tsp salt

200 g butter, cold

200 g quark

For assembly:

jam, Nutella, quark, etc.

1 egg, separated

In a large bowl, whisk together the flour and salt.

Add the cold butter in pieces and rub into the flour mixture with your fingers until you have small flakes.

Make a well in the middle of the flour and add the quark. Mix this gently until a dough forms. Do not overwork the dough or it will become tough.

Press the dough into a disc, wrap with plastic, and chill in the fridge for at least an hour.

Once the dough is cool, roll it out to about ½ cm thick.

It's easiest to use a template to cut out the squares—you can make one of cardboard or paper. The one I used was about 12 x 12 cm (5 inches), but it can be slightly smaller or larger.

Cut out the dough, then put a walnut-sized blob of filling in the middle. Brush the edges with egg white then fold each corn into the middle. Seal with a cut out dough heart (you can freehand this if you don't have a cutter).

Once your Liebesbriefe are sealed, place them on a parchment lined baking sheet. Chill for about half an hour.

Brush them with egg yolk, then bake for about 20 minutes, or until they are golden.

• If you don't feel like making the quark dough, regular puff pastry works well too.

• Use full fat quark (Rahmquark) for best results.

• More info on Quark here.

• Lots of different fillings are possible. You could use jams and jellies, nut butters, Nutella, Ovomaltine Crunchy Cream, and other chocolately spreads, quark or sour cream, even berries and other fruits—go wild. My favourite was half a blob of jam with half a blob of quark (pictured above).