Why it works: Parsley and pepper match in chemistry and in kitchens. They rank in the top 2% of all ingredient pairs, and cooks put them together in 34,122 recipes. Both carry 4'-methylacetophenone, which smells bitter almond. The science ↓
Stuffed Onions, American Style
Ingredients
Directions
The book says “a moderate oven”. The 350°F (175°C) in the steps is the modern equivalent, not the book's own figure.
Prepare the onions
Prepare the onions by draining and cooling them.
Scoop out the center of each onion and chop it finely.
Make the filling
Mix the chopped onion with bread crumbs, mushrooms, fine herbs, Espagnole sauce, parsley, salt, and pepper.
Stuff the mixture into the onions.
Bake and serve
Arrange the stuffed onions in a buttered flat saucepan.
Sprinkle bread crumbs over the onions and place a small piece of butter on top of each.
Bake in a 350°F (175°C) oven until nicely browned.
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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Parsley + peppertop 2% of all pairsSmell alikestrongCooked together34,122 recipes
Shared aroma: 4'-methylacetophenone (bitter almond).
-
Bread + buttertop 7% of all pairsSmell alikemoderateCooked together27,232 recipes
Shared aroma: delta-decalactone (sweet, creamy).
-
Mushroom + buttertop 7% of all pairsSmell alikemoderateCooked together12,525 recipes
Shared aroma: trans-2-decenal (waxy, orange).
-
Onion + parsleytop 9% of all pairsSmell alikemoderateCooked together25,843 recipes
Shared aroma: 2,4-decadienal (seaweed).
-
Bread + mushroomtop 10% of all pairsSmell alikemoderateCooked together2,536 recipes
Shared aroma: 2-nonenal (fatty, green).
Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs
What each ingredient does
- Onions
- Form the edible shell that holds the filling and softens as it bakes.
- Bread crumbs
- Absorb moisture and give the filling body, with crumbs on top for browning.
- Espagnole sauce
- Adds savory depth and moisture to the filling.
- Butter
- Adds fat and richness, and helps the topping brown.
The step that matters
Bake until nicely browned. Baking long enough lets the onions turn tender and the buttered crumbs brown through Maillard reactions. Stopping too early leaves raw, watery onions and a pale top.
Swap the onion
How well each one fits the dish's main ingredients (bread, mushroom, sauce, parsley, pepper, butter):
- Shallotfits better
- Capsicumfits better
- Tomatofits better
- Onionthe original
Fit is the average pairing score against bread, mushroom, sauce, parsley, pepper, butter. 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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