A Spice So Good It's Illegal
Tonka Bean and Apricot Cream Buns
🎉 Welcome to my newsletter, The Boy Who Bakes, a subscriber-supported newsletter, dedicated to all things baked. For more bonus posts, filled with exclusive recipes, you can become a paid subscriber for the weekly newsletter, Second Helpings. It costs just £5 a month and, as well as the weekly recipes, also unlocks access to the full archive of past recipes. To subscribe, to either the paid or free newsletter, click the link below.🎉
Hello, Happy Sunday!
The week's recipe for subscribers of Second Helpings (posted at the end of this newsletter) is inspired by my recent trip to Copenhagen, and it uses a delicious apricot and tonka bean jam, the recipe for which I am including here for all subscribers. If you’ve never tried tonka, this recipe is a great introduction, and the resulting jam is a great way to kick off the summer fruit season, with apricots and strawberries starting to come into season.
Tonka bean is a flavour I am mildly obsessed with; its heady scent is intoxicating and ironically actually toxic. Let me explain. If you know anything about tonka, you’ll surely have heard that it is banned in the US because it is toxic. Whilst this is strictly correct, the full story is a little more complicated. Tonka is only banned in two countries, the US and Belgium. Why is it fine in the rest of the world but banned in these two places? Tonka was banned because it contains a compound called coumarin, which has been shown to be toxic in high doses. The irony here is that America loves cinnamon, a spice that also contains coumarin. A spice that is consumed at a much higher rate than tonka. For those interested, tonka contains 1-3% coumarin, and cassia cinnamon, the most common variety used in the US and in Europe, contains 1%. It is said to be toxic at high doses, affecting the liver, but the aroma of tonka is so strong that only a small amount is ever needed to perfume a recipe. For example, in this recipe, 1 tonka bean is used to make 2 jars of jam. If you ate the entirety of the jam it is possible you’d eat the recommended daily maximum, but you’d never do that. The daily recommended dose is also about cumulative consumption, and I don’t think people would be likely to eat that much each day.
When it comes to the actual flavour of tonka, why is it so special? Why is it so coveted by chefs and perfumers? To me, it is incredibly heady and complex, full of floral vanilla and sweet spices with an almost hay-like woody note as well. The flavour compound responsible for tonka’s flavour is coumarin, which, as mentioned above, is present in many other ingredients, including cacao, which was something I learnt recently, almost by mistake. I attended a chocolate tasting at the excellent William Curley Chocolates, in Soho, organised by my friend Jennifer Earle, who writes The Next Delicious Thing here on Substack. As part of her tasting, Earle showed around a cacao pod, something I have seen hundreds of times before. The pod was old, dried out and well past its prime. Due to the pod's age, I assumed the beans inside wouldn’t have much of an aroma. Whilst most of the flavour compounds which give cacao its flavour had lost their potency, I was surprised to find the cacao beans had a scent incredibly similar to tonka. This sent me down a rabbit hole to confirm that the compound responsible for this unique flavour was in fact shared by both cocoa and tonka: coumarin.
Anyway, back to the jam. Apricot jam is something I normally make with a simple flavouring: just a vanilla pod, the combination of apricot and vanilla being a firm favourite. In this batch I simply swapped the vanilla for tonka, and the resulting jam was incredible, an unusual but incredibly delicious jam perfect for baking or simply served on toast with lots of salted butter.
In this week's Second Helpings newsletter I use that jam to make a recipe inspired by my trip to Copenhagen, a take on the rhubarb cream bun we enjoyed at Juno Bakery. A light milk bun is stuffed with some of the jam and a light-as-air vanilla custard. The rhubarb version we had on the trip was one of my favourite bites, and this recipe feels like a worthy recreation.
Apricot and Tonka Jam
Makes 2x400g jars
750g apricots (weighed without the kernels)
600g caster sugar
Juice of half a lemon
1 tonka bean, finely grated using a microplane or nutmeg grater
When it comes to this jam you have a choice, depending on what you’d like the final consistency to be. If you’re intending to make the second helpings recipe, you’ll need an immersion blender on hand because we’re going to blend it after cooking to make a completely smooth jam. If you just want a delicious jam, I like to cut the apricots in half and then each half into 3 slices. As the jam cooks, you’ll be left with delicious chunks of fruit.
To make the jam, cut the apricots in half and remove the pits. Cut the fruit as desired and add to a large bowl along with the sugar, lemon juice and tonka bean. Stir everything together and leave for a couple of hours to macerate. You can skip this process if you’re in a rush, but this extra step helps to draw out the moisture from the fruit and starts to dissolve the sugar. This means the jam will cook a little quicker, and more importantly, it reduces the chance the sugar will caramelise or burn on the bottom of your pan. With juicy berries I often skip this sip as they release their liquid freely, but apricots need a little helping hand.
When you’re ready to make jam, pour this mixture into a large, heavy-bottomed saucepan and place over a medium/high heat. Cook the mixture, stirring occasionally until the jam is at a rolling boil. Once boiling, the jam will take around 10 minutes to cook. Whilst you can judge the jam visually, I prefer one of the following two methods. Temperature and the wrinkle test. Jam is ready when it reaches between 104ºC and 105ºC. If you have a candy thermometer or an instant-read probe thermometer, this is a great way to check for readiness. If you want to go a little more low-tech, you simply need to place a couple of small plates into the freezer before you start making the jam. Once the jam has been boiling for a while, you can spoon a little onto one of the chilled plates and let it sit for a minute before pushing it with your finger. If the skin of the jam wrinkles, the jam is ready and will set as it cools.
Once the jam is ready, remove the pot from the heat and leave for a couple of minutes. At this stage, if using the jam in this week's Second Helpings recipe, use an immersion blender to blend the jam to make it nice and smooth. Pour the jam into two sterilised jars and seal. If properly sealed, this jam will keep for many months.
Keep reading with a 7-day free trial
Subscribe to The Boy Who Bakes to keep reading this post and get 7 days of free access to the full post archives.