Rhubarb Pie

Mix granulated sugar A and pectin in a small bowl – this reduces the risk of the pectin clumping when you pour it into the hot purée.

Pour the rhubarb purée into a saucepan and heat over medium-high heat.

Once the purée reaches 40°C (104°F), add the pectin and sugar mixture (40°C is a well-tested temperature – if it's too hot the pectin can clump, and you don't want that).

Once the mixture starts to bubble slightly, add the glucose syrup.

Bring it to a boil, then add granulated sugar B – but don't pour it all in at once, as that will drop the temperature too much and the pectin could start to set prematurely.

Three to four batches of sugar work well – make sure it's bubbling again slightly before adding the next batch.

Cook everything over medium-high heat to 107°C (225°F).

Once you reach this temperature, add the acid solution (I use citric acid, but you can use whichever acid you like – the acid lowers the pH of the marmalade mixture so the pectin can work as effectively as possible). If you don't have any acid available, 18 grams0.63 oz of lemon juice works too.

Once the marmalade has cooled, blend it so it becomes pipeable.

Pipe about 3 grams per shell.

Start by letting the vanilla steep in the cream for 24 hours – pour 100 grams3.53 oz of cream into a small saucepan or container, scrape out the vanilla bean, and add both the seeds and the scraped pod to the cream.

Cover with plastic wrap and place in the fridge.

Once that's done, you can gently warm the cream – this releases more of the cream the vanilla bean has absorbed.

Weigh the cream once you've removed the vanilla bean – it will likely be less than 100 grams3.53 oz. If you have 95 grams3.35 oz, top it up with 5 grams0.176 oz more.

Pour the yogurt powder, glucose syrup, sorbitol powder, and invert sugar into the vanilla cream and heat to 40°C (104°F).

Melt the white chocolate to 40°C (104°F) and mix with the cream and sugar mixture.

Blend with an immersion blender to achieve a good emulsion.

Once the ganache has cooled and is between 30-32°C (86-90°F), add the butter – make sure it's at room temperature so it's easy to blend into the ganache.

Add the butter a little at a time, making sure the ganache is homogeneous before adding more – four to five additions of butter work well.

Let the ganache cool to 29°C (84°F), then pipe a little into the bonbon shells, about 4 grams per shell – leave some room for the crisp layer.

If you don't have yogurt powder, sorbitol powder, or invert sugar, you can skip them – but make sure to use the glucose syrup regardless. Without the sorbitol powder and invert sugar, the ganache will keep for about a month.

Make a crumble dough with the flour, granulated sugar, butter, and cardamom.

Bake in the oven at 225°C (435°F) for 15-20 minutes – if you have a convection oven, keep an eye on the "dough," as 10 minutes may be enough depending on how large your "crumbs" are.

Have your own favorite recipe with different flavors? Feel free to use that instead!

Once the crumble is baked, let it cool, then blend it if the "crumbs" are too large to pipe.

Melt the cocoa butter with the ghee, mix in the salt and the oil, and then the baked crumble.

Make sure the mixture becomes homogeneous, and ideally pre-crystallize it before filling the rest of the bonbon with it, about 2.5 grams per shell. It's fine without that too, but it shouldn't be above 29°C (84°F) when you pipe it.

As you may notice, this is a crisp layer with no chocolate at all – the idea is to give part of the bonbon a taste that isn't overly sweet. There's a lot of fat in this crisp, but it doesn't taste strange alongside the bonbon's other layers.

Once the crisp layer has set, you can seal the bonbons and then pop them out once they're ready!