Save to Pinterest My neighbor handed me a bundle of rhubarb over the fence one April morning, pink stalks still damp with dew. I had white chocolate left from Easter and a bottle of elderflower cordial I'd been hoarding since summer. What started as pantry roulette turned into the most elegant tart I've ever pulled from my oven. The kitchen smelled like spring itself, floral and bright, and I knew I'd struck something special.
I brought this tart to a garden party where everyone else had store-bought desserts. By the time I sliced the first piece, three people were hovering with phones out, snapping pictures of the rosy rhubarb glistening on top. Someone asked if I'd trained in Paris. I just laughed and said I'd trained in desperation with an overgrown rhubarb plant.
Ingredients
- All-purpose flour (200 g): The foundation of your buttery crust, this creates the crisp shell that holds everything together without competing with the delicate filling.
- Cold unsalted butter (100 g, cubed): Keep it icy cold so it creates flaky layers instead of melting into the dough, the secret to pastry that shatters under your fork.
- Powdered sugar (50 g): Dissolves more easily than granulated and gives the crust a tender, almost shortbread-like texture.
- Egg yolk (1 large): Adds richness and helps bind the dough without making it tough, the glue that holds your tart shell dreams together.
- Cold water (1 to 2 tbsp): Just enough to bring the dough together, too much and you'll end up with a tough crust instead of a crisp one.
- Salt (pinch): Don't skip this, it wakes up the butter flavor and keeps the crust from tasting flat.
- White chocolate (150 g, finely chopped): Use good quality stuff, not candy melts, because it becomes the soul of your custard and cheap chocolate tastes waxy.
- Heavy cream (250 ml): The luxurious base of your custard, this gives it body and a silky mouthfeel that coats your spoon.
- Whole milk (50 ml): Thins the custard just enough so it's creamy, not gluey, and helps it set to the perfect firmness.
- Elderflower cordial (60 ml for custard, 2 tbsp for rhubarb): This is where the magic lives, floral and honey-sweet, it makes the whole tart smell like an English garden in June.
- Egg yolks (3 large): The thickening agents that transform cream into custard, whisk them well or you'll get scrambled eggs instead of silk.
- Granulated sugar (30 g for custard, 60 g for rhubarb): Sweetens and helps the custard set, and coaxes the rhubarb into tender submission without turning it to mush.
- Vanilla extract (1 tsp): A warm undertone that rounds out the floral notes and makes the white chocolate taste even creamier.
- Rhubarb (300 g, trimmed and cut into 5 cm batons): The tart, rosy star of the show, it holds its shape when roasted and provides the acidic punch that keeps this dessert from being too sweet.
- Lemon zest (from 1 lemon): Brightens the rhubarb and adds a citrus note that plays beautifully with elderflower.
Instructions
- Make the Tart Crust:
- Pulse the flour, cold butter cubes, powdered sugar, and salt in your food processor until it looks like coarse breadcrumbs, then add the egg yolk and a tablespoon of cold water, pulsing just until the dough starts clumping together. Shape it into a disk, wrap it in plastic, and let it chill for 30 minutes so the gluten relaxes and the butter firms up.
- Blind Bake the Shell:
- Roll the chilled dough out on a floured surface until it's big enough to fit your 23 cm tart tin, press it in gently, trim the edges, and chill it again for 15 minutes. Line it with parchment, fill it with baking beans, and bake at 180°C for 15 minutes, then remove the beans and parchment and bake another 5 to 7 minutes until the crust turns golden and smells like butter and heaven.
- Prepare the Custard Base:
- Heat the cream and milk in a saucepan until it's steaming but not boiling, while you whisk the egg yolks, sugar, and vanilla in a bowl until they're pale and thick. Slowly pour the hot cream into the yolks, whisking constantly so they temper instead of scrambling, then return everything to the pan and stir over low heat until the mixture coats the back of a spoon.
- Finish the Custard:
- Take the custard off the heat and stir in the chopped white chocolate and elderflower cordial, whisking until it's completely smooth and glossy. Pour it into your cooled tart shell and slide the whole thing into the fridge for at least an hour until it sets firm.
- Roast the Rhubarb:
- Lay the rhubarb batons in a single layer in a baking dish, sprinkle them with sugar and lemon zest, drizzle with elderflower cordial, and cover with foil. Roast at 190°C for 15 minutes, then uncover and roast another 5 to 8 minutes until the rhubarb is tender but still holding its shape, not collapsing into jam.
- Assemble and Chill:
- Once the rhubarb has cooled completely, arrange the batons over the set custard in whatever pattern makes your heart happy. If you want extra shine, brush them lightly with a bit more elderflower cordial, then chill until you're ready to slice and serve.
Save to Pinterest The first time I served this, my friend who claims she hates rhubarb ate two slices and asked for the recipe. She said the elderflower made it taste like eating flowers without the weird texture. I watched her scrape her fork across the plate to catch every last crumb of crust, and I realized this tart had converted a skeptic into a believer.
Choosing Your Rhubarb
Look for stalks that are firm and brightly colored, either crimson or pink with a bit of green. Thin stalks tend to be more tender and less fibrous than the thick woody ones. If your rhubarb is very tart, you can increase the sugar slightly when roasting, but I like the pucker it brings to balance the sweet custard.
Making It Ahead
The tart shell can be baked and stored in an airtight container for two days. The custard can be made and poured into the shell a day ahead, and the rhubarb can be roasted the morning of serving. Just keep everything chilled and assemble a few hours before your guests arrive, giving the flavors time to settle into each other.
Serving Suggestions
This tart is stunning on its own, but a dollop of lightly sweetened whipped cream or a scoop of vanilla ice cream turns it into something people remember for months. I've also scattered toasted pistachios over the top for a bit of crunch and a pop of green that makes it look even more springlike.
- Serve it cold or at cool room temperature, never warm or the custard will lose its set.
- Pair it with a glass of Moscato, elderflower spritz, or even a floral gin and tonic.
- Leftovers keep for up to three days in the fridge, covered loosely so the crust doesn't get soggy.
Save to Pinterest Every time I make this tart, I'm reminded that the best desserts come from happy accidents and ingredients you didn't plan to use together. It's become my go-to when I want to impress without pretending I'm someone I'm not.
Recipe FAQs
- → Can I make this tart ahead of time?
Yes, this tart is perfect for making ahead. Prepare the tart shell and custard up to 24 hours in advance, keeping it refrigerated. Roast the rhubarb separately and arrange it on top a few hours before serving for best presentation.
- → What can I substitute for elderflower cordial?
You can use rose water, orange blossom water, or even a light lemon syrup as alternatives. Start with smaller amounts as these flavors can be quite strong. Vanilla extract alone also works beautifully with white chocolate.
- → How do I prevent the tart crust from becoming soggy?
Blind baking the crust until fully golden ensures a crisp base. Make sure the crust is completely cooled before adding the custard. You can also brush the baked shell with a thin layer of melted white chocolate for extra protection.
- → Can I use frozen rhubarb instead of fresh?
Fresh rhubarb works best for this tart as it holds its shape better when roasted. If using frozen, thaw and drain excess moisture thoroughly, then reduce roasting time to prevent it from becoming too soft and mushy.
- → How long will this tart keep in the refrigerator?
The assembled tart keeps well for up to 2 days when stored covered in the refrigerator. The rhubarb may release some juice over time, so for best results, serve within 24 hours of assembling.
- → What type of white chocolate should I use?
Choose good quality white chocolate with at least 25% cocoa butter for the smoothest custard. Avoid white baking chips as they contain stabilizers that prevent proper melting. Brands like Lindt or Valrhona work exceptionally well.