Why it works: Rhubarb and lemon match in chemistry and in kitchens. They rank in the top 7% of all ingredient pairs, and cooks put them together in 546 recipes. Both carry acetic acid, which smells sour, vinegar. The science ↓
Rhubarb Tart
Ingredients
Directions
The book gives no oven temperature. The 400°F (200°C) in the steps was added when the recipe was transcribed, as a starting point.
Prepare
Preheat the oven to 400°F (200°C).
Make the puff pastry and line the edges of a deep pie dish with it.
Wash, wipe, and cut the rhubarb into 1-inch pieces. If the rhubarb is tough, peel off the outer skin.
Fill and bake
Pile the rhubarb high in the dish, as it will shrink during cooking.
Add the sugar on top of the rhubarb and cover with the pastry crust. Decorate the edges of the crust and bake for 45 minutes.
Optionally, add a small amount of lemon juice and minced lemon peel for extra flavor.
Glaze and finish
Brush the tart with beaten egg white. Sprinkle sifted sugar over the tart.
Return the tart to the oven for a few minutes to set the glaze.
Transcribed from a scanned cookbook and modernised for today's kitchens. Where the book gave no heat or time, or said "a moderate oven", the temperatures and times here may be modern equivalents rather than the book's own figures.
Explore the science
The flavor team
The pairs that carry this dish. Each one is judged two ways: how much their aromas overlap, and how often cooks already put them together.
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Rhubarb + lemontop 7% of all pairsSmell alikestrongCooked together546 recipes
Shared aroma: acetic acid (sour, vinegar).
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Sugar + lemontop 18% of all pairsSmell alikelowCooked together53,532 recipes
Shared aroma: 2-nonenal (fatty, green).
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Rhubarb + sugartop 18% of all pairsSmell alikemoderateCooked together1,852 recipes
Shared aroma: 1-penten-3-one (fish, pungent).
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Egg + lemontop 19% of all pairsSmell alikelowCooked together44,316 recipes
Shared aroma: (e,e)-2,4-decadienal (fatty, deep fried).
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Sugar + eggtop 21% of all pairsSmell alikemoderateCooked together122,807 recipes
Shared aroma: 2-nonenal (fatty, green).
Sugar and lemon barely smell alike, yet cooks put them together in 53,532 recipes: they work on texture and structure more than aroma.
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Rhubarb
- Provides the tart filling's sharp flavor and bulk that shrinks as it cooks.
- Puff pastry
- Forms the flaky, buttery crust that encloses the filling.
- Moist sugar
- Sweetens the rhubarb and draws out juice that forms a syrupy filling.
- Egg white
- Brushed on top, it helps the crust brown and set a glossy glaze.
The step that matters
Pile the rhubarb high in the dish. Rhubarb shrinks considerably as it cooks, so a low fill will leave a sunken, gappy tart once baked. Heaping it up lets the filling settle to the right level.
Swap the lemon
The recipe marks lemon as optional. How well each one fits the dish's main ingredients (rhubarb, sugar, egg):
- Vanillafits better
- Raisinfits about as well
- Lemonthe original
- Figfits about as well
Fit is the average pairing score against rhubarb, sugar, egg. Candidates are from the same food group and used in at least 100 recipes.
“What each ingredient does” and “The step that matters” were written by Claude from this recipe’s own method and reviewed in samples by CompKitchen.
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