Save on Pinterest My neighbor knocked on my door one April morning holding a bundle of rhubarb stalks from her garden, ruby-pink and beautiful. I'd never cooked with rhubarb before, but she insisted I try roasting it with something floral. That afternoon, I paired it with white chocolate and elderflower, and the combination was so unexpectedly elegant that I made it again for a dinner party that same weekend. Now it's my signature spring dessert.
The first time I served this, my friend who claims to hate rhubarb asked for the recipe before dessert plates were cleared. She said the roasted batons reminded her of candied ginger, sweet and sharp at once. I watched her take a second slice and realized this tart has a way of converting people. It's become my go-to when I want to impress without the stress of last-minute assembly.
Ingredients
- All-purpose flour: The foundation of a tender, crumbly crust that holds its shape without turning tough or dense.
- Cold unsalted butter: Cubed and kept icy cold, it creates those flaky pockets that make pastry worth the effort.
- Powdered sugar: Dissolves more smoothly than granulated, giving the crust a melt-in-your-mouth sweetness.
- Egg yolk: Binds the dough and adds richness without making it chewy or bread-like.
- Cold water: Just enough to bring the dough together, add it slowly so you don't overwork the pastry.
- Salt: A small pinch sharpens the sweetness and balances the buttery richness.
- White chocolate: Choose a good quality bar with cocoa butter listed first, it melts into the custard like silk.
- Heavy cream: The backbone of the custard, lending body and a luxurious mouthfeel.
- Whole milk: Thins the cream just enough so the custard sets without turning too stiff.
- Elderflower cordial: This is where the magic happens, floral and honeyed, it lifts the whole tart into springtime.
- Egg yolks: They thicken the custard gently and give it that pale, creamy color.
- Granulated sugar: Sweetens the custard and the rhubarb, each in their own measured way.
- Vanilla extract: A quiet background note that rounds out the white chocolate without competing.
- Rhubarb: Look for firm, bright stalks and cut them into even batons so they roast uniformly.
- Lemon zest: Brightens the rhubarb and keeps it from tasting flat or one-dimensional.
Instructions
- Mix and Chill the Dough:
- Pulse the flour, cold butter, powdered sugar, and salt until the mixture looks like damp sand, then add the egg yolk and just enough cold water to make it clump together. Wrap the dough tightly and let it rest in the fridge so the gluten relaxes and the butter firms up again.
- Roll and Blind Bake the Crust:
- Roll the chilled dough out on a floured counter, press it gently into your tart tin, and trim the edges with a sharp knife. Line it with parchment, fill with baking beans, and bake until the edges turn golden, then remove the beans and bake a few minutes more until the base is crisp and lightly colored.
- Warm the Cream and Temper the Yolks:
- Heat the cream and milk until you see steam rising, then slowly pour it into the whisked yolks and sugar while stirring constantly so the eggs don't scramble. Return everything to the pan and stir over low heat until the custard thickens just enough to coat the back of a spoon.
- Melt in the Chocolate and Elderflower:
- Take the custard off the heat and stir in the chopped white chocolate and elderflower cordial until the mixture turns glossy and smooth. Pour it into the cooled tart shell and chill until firm, at least an hour.
- Roast the Rhubarb:
- Lay the rhubarb batons in a single layer in a baking dish, sprinkle with sugar and lemon zest, and drizzle with elderflower cordial. Cover with foil and roast until tender but still holding their shape, then let them cool completely before arranging on top of the set custard.
Save on Pinterest I brought this tart to a friend's baby shower last May, and the host's grandmother told me it reminded her of the elderflower drinks she had as a girl in the English countryside. She took a photo of the tart before we cut into it, and I realized then that some desserts carry more than flavor. They hold memories, seasons, and quiet connections between strangers who share a slice.
Make-Ahead Magic
This tart is built for advance preparation, which is why it's saved me more than once when hosting. The crust can be baked and cooled a day ahead, wrapped tightly and kept at room temperature. The custard filling also keeps beautifully for a day in the fridge once set in the shell. Roast the rhubarb the morning of your event, let it cool, and arrange it on the tart an hour before serving so it looks fresh and jewel-bright.
Flavor Swaps and Additions
If rhubarb isn't in season, roasted strawberries work just as well and carry the same balance of sweetness and tang. You can replace the elderflower cordial with a tablespoon of rose water or orange blossom water for a different floral note. I've also sprinkled toasted pistachios over the top for a bit of crunch and a pop of green that makes the whole tart feel even more springlike.
Serving and Storing
Slice this tart with a sharp knife wiped clean between cuts so each piece looks neat and professional. Serve it chilled or at cool room temperature with a small dollop of lightly whipped cream or a glass of chilled Moscato. Leftovers keep in the fridge for up to two days, though the crust will soften slightly as it sits.
- Let the tart sit at room temperature for ten minutes before slicing so the custard isn't too firm.
- If you're transporting it, keep the rhubarb separate and arrange it just before serving so it doesn't bleed into the custard.
- A light dusting of powdered sugar over the rhubarb right before serving adds a delicate finishing touch.
Save on Pinterest There's something about the way the pink rhubarb sits on top of that pale custard that makes every slice feel like a small celebration. I hope this tart finds its way onto your table when the weather warms and the first spring produce starts appearing at the market.
Recipe Questions & Answers
- → Can I make this tart ahead of time?
Yes, this tart is perfect for advance preparation. The custard-filled tart shell can be made up to 24 hours ahead and stored in the refrigerator. Add the roasted rhubarb topping a few hours before serving for best presentation and texture.
- → What can I substitute for elderflower cordial?
If elderflower cordial is unavailable, try using a combination of lemon juice and honey, or a splash of St. Germain liqueur. You can also use orange blossom water for a different floral note, though the flavor profile will change slightly.
- → How do I prevent the tart crust from becoming soggy?
Blind baking the crust completely until golden is essential. Additionally, ensure the crust is fully cooled before adding the custard, and let the custard set completely in the refrigerator. The roasted rhubarb should also be cooled and drained of excess liquid before arranging on top.
- → 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 completely and pat dry with paper towels to remove excess moisture. You may need to reduce roasting time slightly as frozen rhubarb tends to be softer.
- → What type of white chocolate works best for the custard?
Use good quality white chocolate with at least 25-30% cocoa butter for the smoothest, creamiest custard. Avoid white chocolate chips or candy melts, as they contain stabilizers that can affect the texture. Brands like Valrhona, Lindt, or Callebaut work exceptionally well.
- → How should I store leftover tart?
Cover the tart loosely with plastic wrap or store in an airtight container in the refrigerator for up to 3 days. The rhubarb may release some liquid over time, so it's best enjoyed within 1-2 days of assembly for optimal texture and appearance.