Name: Roast Beef and Caramelized Onion Panini
Ingredients: 3 Tbs. olive oil, plus more for brushing; 2 large yellow onions, about 1 1/2 lb. total, halved; lengthwise and very thinly sliced; 2 slices country-style bread, each 1/2 inch thick; 2 Tbs. mayonnaise; 2 thin slices roast beef; Salt and freshly ground pepper, to taste; 1 slice aged cheddar cheese; 4 thin slices Granny Smith apple

Why it works: Onion and beef are a kitchen classic. They rank in the top 7% of all ingredient pairs, and cooks put them together in 17,092 recipes. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓

Roast Beef and Caramelized Onion Panini

Ingredients

3 Tbs. olive oil, plus more for brushing
2 large yellow onions, about 1 1/2 lb. total, halved
lengthwise and very thinly sliced
2 slices country-style bread, each 1/2 inch thick
2 Tbs. mayonnaise
2 thin slices roast beef
Salt and freshly ground pepper, to taste
1 slice aged cheddar cheese
4 thin slices Granny Smith apple

Directions

Step-by-step directions aren't available for this recipe. See the full recipe at the source →

Nutrition, whole recipe (rough)

1160Calories

54 gProtein

45 gFat

132 gCarbs

What these numbers assume: 9 portions

Ingredient	Portion assumed	kcal
Flour	1 cup (125g) all-purpose	455
Beef	100g cooked	250
Olive Oil	1 tbsp (14g)	119
Cheddar Cheese	1 oz (28g)	113
Apple	1 medium (182g)	95
Egg	1 large egg (50g)	78
Onion	1 medium (110g)	44
Black Pepper	1 tsp ground (2.3g)	6
Salt	1 tsp (6g)	0

One typical portion per ingredient; the recipe's quantities are not counted. A rough guide only, not for medical or dietary planning.

By williamssonoma. Recipe from Open Recipes.

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.

Onion + beeftop 7% of all pairs

Smell alikemoderate

Cooked together17,092 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Olive + oniontop 8% of all pairs

Smell alikemoderate

Cooked together29,779 recipes

Shared aroma: 2,4-decadienal (seaweed).
Olive + breadtop 9% of all pairs

Smell alikemoderate

Cooked together1,091 recipes

Shared aroma: 2-undecenal (sweet).
Beef + peppertop 10% of all pairs

Smell alikemoderate

Cooked together18,971 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Cheddar cheese + appletop 11% of all pairs

Smell alikemoderate

Cooked together133 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).

Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs

Swap the apple

How well each one fits the dish's main ingredients (olive, onion, bread, beef, pepper, cheddar cheese):

Avocadofits better
Plumfits better
Limefits better
Applethe original

Fit is the average pairing score against olive, onion, bread, beef, pepper, cheddar cheese. Candidates are from the same food group and used in at least 100 recipes.

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