Rhubarb White Chocolate Elderflower Tart

The first rhubarb of spring always catches me off guard, those bright pink stalks appearing at the market when everything else is still gray and cautious. I bought a bundle on impulse one Saturday, not entirely sure what I'd do with it, and ended up turning my kitchen into a fragrant cloud of elderflower and vanilla. The tart that emerged from the oven that afternoon, with its jewel-toned rhubarb gleaming on top, looked far fancier than anything I thought I could pull off. My neighbor, peeking through the window, asked if I was opening a bakery.

I made this tart for my sister's birthday dinner last May, and she still brings it up whenever dessert is mentioned. She's not usually one for flowery flavors, but something about the tangy rhubarb cutting through the creamy custard won her over completely. We ate it outside as the sun set, and the tartness felt just right against the warm evening air. I remember scraping the last crumbs from my plate, already planning when I'd make it again.

Ingredients

• All-purpose flour: The foundation of your crust, and using cold ingredients here is non-negotiable for that crisp, flaky texture.
• Cold unsalted butter: Cubed small so it distributes evenly, creating those lovely layers when it melts in the oven.
• Powdered sugar: Gives the crust a delicate sweetness and tender crumb that holds up beautifully to the creamy filling.
• Egg yolk: Binds the dough without making it tough, and adds richness that complements the buttery notes.
• White chocolate: Choose a good quality brand, it melts into the custard and brings a subtle sweetness that doesn't overpower the elderflower.
• Heavy cream and whole milk: The base of your custard, creating that silky texture that sets just firm enough to slice cleanly.
• Elderflower cordial: This is where the magic happens, infusing everything with a gentle floral note that tastes like a garden in June.
• Rhubarb: Look for stalks that are firm and brightly colored, they roast into tender batons that hold their shape and add gorgeous color.
• Lemon zest: A small addition that brightens the rhubarb and keeps the sweetness in check.

Instructions

Mix the tart dough:

Pulse the flour, butter, sugar, and salt in your food processor until it looks like coarse sand, then add the egg yolk and just enough cold water to bring it together. The dough should feel slightly crumbly but hold when pressed, not wet or sticky.

Chill and roll:

Let the dough rest in the fridge wrapped tightly, this relaxes the gluten and makes rolling so much easier. When you roll it out, work quickly on a floured surface and aim for even thickness so it bakes uniformly.

Blind bake the crust:

Press the dough into your tart tin, prick the base with a fork, then line with parchment and fill with baking beans to keep it flat. After the first bake, remove the beans and let it color gently until golden and crisp all over.

Prepare the custard base:

Heat your cream and milk until steaming, then temper the egg yolks by whisking in the hot liquid slowly to avoid scrambling. Stir over low heat until it thickens just enough to coat the back of a spoon, patience here prevents curdling.

Finish the custard:

Off the heat, stir in the chopped white chocolate and elderflower cordial until completely smooth and glossy. Pour it into your cooled tart shell and let it chill until firm, at least an hour but longer is fine.

Roast the rhubarb:

Arrange the rhubarb in a single layer, sprinkle with sugar and lemon zest, then cover with foil to steam gently before uncovering to caramelize slightly. You want it tender but still holding its shape, not mushy.

Assemble and chill:

Once everything is cool, arrange the rhubarb over the set custard in whatever pattern makes you happy. A quick brush of elderflower cordial adds shine and a final floral note before serving.

Save

There is something deeply satisfying about slicing into this tart and seeing the clean layers, the golden crust giving way to pale custard and bright rhubarb on top. It became my go-to whenever I wanted to mark an occasion without spending all day in the kitchen. The compliments always feel disproportionate to the effort, which is exactly the kind of recipe I love to keep in rotation.

Choosing Your Rhubarb

Early season rhubarb tends to be the most tender and pink, while later stalks can be thicker and more green but still delicious. I look for stalks that are firm and glossy, avoiding any that feel rubbery or have lots of blemishes. If your rhubarb is especially thick, you might want to halve the batons lengthwise so they roast evenly. The color doesn't affect the flavor as much as you'd think, green rhubarb is just as tart and lovely as the pink varieties.

Make Ahead Strategy

This tart is a dream for entertaining because almost everything can be done in advance. The crust can be baked a day ahead and stored at room temperature, and the custard filling sets beautifully overnight in the fridge. I often roast the rhubarb the morning of serving and assemble everything a few hours before guests arrive. The flavors actually improve with a little time, the elderflower mellows and everything melds together in a way that tastes more cohesive.

Serving Suggestions

A small dollop of lightly whipped cream on the side cuts through the richness beautifully, though the tart is plenty indulgent on its own. I have also served it with a scoop of vanilla ice cream, which melts into the custard and creates a luxurious puddle on the plate. For a fancy touch, scatter a handful of toasted pistachios or sliced almonds over the top just before serving.

• Pair with a chilled glass of Moscato or a sparkling elderflower drink for a perfect flavor echo.
• Leftovers keep well in the fridge for up to three days, covered loosely with plastic wrap.
• If rhubarb is out of season, roasted strawberries or poached pears make a beautiful substitution.

Save

This tart has become my way of welcoming spring, a little celebration of the season's first bright flavors after months of root vegetables and hearty stews. I hope it brings as much joy to your table as it has to mine.

Recipe FAQs

→ Can I make this tart ahead of time?

Yes, this tart is perfect for making ahead. The crust and custard can be prepared up to 24 hours in advance, and the roasted rhubarb can be made a day ahead and stored in the refrigerator. Assemble the tart up to 4 hours before serving for best results.

→ What can I substitute for elderflower cordial?

If elderflower cordial is unavailable, you can substitute with a combination of lemon juice and honey, or use rose water for a different floral note. Alternatively, omit it entirely and increase the vanilla extract for a classic white chocolate custard.

→ How do I prevent the tart crust from becoming soggy?

Blind baking the crust until golden and completely cooled before adding the custard is essential. You can also brush the baked crust with a thin layer of melted white chocolate before adding the custard for extra protection against moisture.

→ Can I use frozen rhubarb instead of fresh?

Yes, frozen rhubarb can be used. Thaw it completely and drain excess liquid before roasting. You may need to reduce the roasting time slightly as frozen rhubarb tends to soften more quickly than fresh.

→ How should I store leftover tart?

Store any leftover tart covered in the refrigerator for up to 3 days. The custard will remain creamy, though the crust may soften slightly over time. For best texture, consume within 2 days of assembly.

→ What type of white chocolate works best for the custard?

Use good quality white chocolate with at least 28% cocoa butter for the best flavor and texture. Avoid white chocolate chips, as they often contain stabilizers that prevent smooth melting. Brands like Lindt, Valrhona, or Callebaut work excellently.