As food geeks, we all have a few ‘fun facts’ up our sleeve, right? Random snippets of foodie info that we use to pepper the conversations at parties or liven up a boring first date? Don’t tell me you’ve never reached for a bit of asparagus-related trivia to brighten up a dull moment, or quietened a room by pointing out that red Skittles are coloured with smushed-up insects. If you haven’t, I’m certainly never going to a party with you.
One of my favourites to trot out on such occasions is the fact that there are no naturally blue foods. There is a reason that Nestlé removed blue Smarties from circulation around 2006 after it replaced all its artificial colours with natural varieties. It took them two years to source a natural replacement, derived from a bacterium. ‘BUT, BLUEBERRIES’ is the inevitable response, for which I have an excellent counter-attack. Blueberries are not, really, blue. They are more of a dark purple colour. Have you ever eaten too many and looked at your tongue?
Last August I spent a happy week in Finland, bathing in the ferociously cold sea, admiring the old communist architecture, enjoying the legendary Finnish fear of social interaction and gorging myself on wild blueberries, fresh from the market. They left me with a happy soul and a vivid dark-purple tongue. I tried to take a photo of it to send to the man I had very recently started dating. In case you’re wondering, it’s really very difficult to take a selfie with your indigo tongue sticking out that is somehow both sexy and quirky, and moreover disguises the fact that you are in a closet-sized hostel toilet in Helsinki. I managed, readers, don’t fret, but it was a challenge.
Transporting approximately a kilo of these wild blueberries back on the plane to Denmark was also a challenge, and the inside of my handbag still bears the purple scars. It was worth it, though. I squirrelled them away in my freezer and have been slowly eking them out over a period of nine months or so. Much smaller and firmer than the mass-produced, inflated and often tasteless specimens we can buy year-round in supermarkets, this seasonal Scandinavian delicacy is tart and deeply flavoursome, swollen with tart purple (NOT BLUE) juice. It is a blueberry as a blueberry once was, before commercial mass production took over and we started to ship fat, watery varieties in from foreign climes.
The best way to enjoy the flavour of these beauties is simply as is, or in a simple compote made by simmering them with a little sugar and a tiny drop of water. I decided to go a step further and swirl this gorgeous vivid mass of juice and berries through a creamy lemon cheesecake. I found a bunch of squat, bright marigold yellow Persian lemons at the farmer’s market. Their flavour is delightfully fragrant; slightly sweet, with a hint of the bergamot. Their zest and juice is perfect rippled through a creamy, gelatine-set cheesecake mix. This is my go-to cheesecake recipe, and it gives wonderfully light results, a nice change from the heavier baked variety. Garnish with lemon balm or lemon verbena, or even lemon thyme: the herbal kick works wonderfully against the tart, fruit-rippled filling and also adds a pop of vivid green colour.
Special wild blueberries, special Persian lemons: a special springtime treat. And make sure to bore whomever you serve it to with some fun facts about the colour blue in nature (less than 10% of all flowering plants produce blue flowers, for example. You’re welcome).
Persian sweet lemon and wild blueberry cheesecake (serves 6):
- 120g wild (or normal) blueberries
- 3 tsp caster sugar
- 1 tbsp arrowroot or cornflour
- 150g Digestive biscuits
- 50g butter, melted
- 180g icing sugar, plus extra for dusting
- 450g quark soft cheese (or cottage cheese blitzed to smooth in a blender)
- 200g cream cheese (full fat)
- Zest of 2 lemons
- 4 gelatine sheets
- Juice of 2 lemons
- Baby lemon balm or lemon verbena leaves, to decorate
- Strips of lemon zest, to decorate
First, make the blueberry compote. Put the berries in a saucepan with the sugar and bring to the boil. Turn down the heat and simmer for a few minutes until just burst and juicy. Add the arrowroot or cornflour (if using cornflour, mix with an equal amount of water to make a paste before adding it), stir thoroughly to thicken, then set aside to cool.
Pre-heat the oven to 180C. Grease and line the bottom of a 20cm springform cake tin with greaseproof paper. Blitz the biscuits to fine crumbs in a food processor. Add the melted butter and blitz briefly to combine. Tip into the prepared tin, press down over the bottom of the tin with the back of a spoon to level, then bake for 10 minutes. Remove and leave to cool.
Whisk together the icing sugar, quark, cream cheese and lemon zest. Soak the gelatine sheets in cold water for a few minutes to soften. Place the lemon juice in a small saucepan and heat gently. Add the gelatine and whisk until dissolved. Whisk this into the cheese mixture, and beat thoroughly to combine. Swirl the blueberry compote through the cheese mixture, leaving bright streaks (don’t mix it completely). Pour into the cake tin, place in the fridge and chill for at least 6 hours.
Decorate with strips of lemon zest, a dusting of icing sugar and some baby lemon balm or lemon verbena leaves before serving.