Equipment
Ingredients
Roasted Squash
- 1 butternut squash, peeled, seeded, and cut into 1.5 cm cubes
- 30 ml olive oil
- 2 g fine sea salt
- ½ g black pepper, freshly cracked
Caramelized Onion and Tomato Base
- 2 yellow onion, thinly sliced
- 30 ml olive oil
- 2 g fine sea salt
- 3 plum tomato, cored and finely diced
Agrodolce and Aromatics
- 50 g golden raisins
- 30 g capers, drained and rinsed
- 60 ml red wine vinegar
- 35 g granulated sugar
- 10 g fresh mint, finely chopped leaves
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 194 kcal
- Protein
- 2 g
- Carbohydrates
- 28 g
- Fat
- 9 g
- Fiber
- 4 g
- Sodium
- 389 mg
- Saturated Fat
- 1 g
- Potassium
- 578 mg
- Calcium
- 65 mg
- Iron
- 1.3 mg
- Magnesium
- 37 mg
- Phosphorus
- 36 mg
- Zinc
- 0.2 mg
- Vitamin A
- 422 mcg
- Vitamin C
- 26 mg
- Water
- 124 g
Sources: Aggregated Public Data, USDA FoodData Central
Method
Preheat the oven to 200°C (400°F) and line a large baking sheet with parchment paper.
Peel, seed, and dice the butternut squash into uniform 1.5 cm cubes on a cutting board using a vegetable peeler and chef's knife.
Toss the diced squash with 30 ml olive oil, 2 g fine sea salt, and 0.5 g black pepper directly on the prepared baking sheet in an even layer.
Roast the squash in the oven at 200°C (400°F) for 25 minutes, turning once at the 15-minute mark, until the edges are golden brown and tender.
Heat 30 ml olive oil in a heavy-bottomed skillet over medium-low heat at 150°C (300°F), then cook the sliced yellow onions with 2 g fine sea salt for 20 minutes, stirring frequently with a wooden spoon, until deeply caramelized and jammy.
Stir the diced plum tomatoes, 50 g golden raisins, and 30 g drained capers into the skillet and simmer over medium heat at 100°C (212°F) for 8 minutes until the tomatoes break down into a loose sauce.
Add 60 ml red wine vinegar and 35 g granulated sugar to the skillet and reduce over medium heat at 100°C (212°F) for 4 minutes, stirring constantly until syrupy and clear of raw vinegar harshness.
Add the roasted butternut squash to the skillet and gently fold into the warm agrodolce mixture using a wooden spoon to coat every cube without breaking the squash.
Simmer the combined relish over low heat at 90°C (194°F) for 3 minutes to allow the squash to absorb the sweet and sour pan juices.
Remove the skillet from the heat, gently fold in 10 g finely chopped fresh mint, and allow the relish to cool for 15 minutes before serving at room temperature or cooling completely for storage.
Chef's Notes
- Roasting the squash separately rather than stewing it prevents the vegetable from dissolving into a puree and creates flavorful browned edges.
- Always rinse salt-packed or brine-packed capers thoroughly under cold running water to avoid over-salting the agrodolce balance.
- This relish develops superior flavor after resting; making it a day ahead allows the raisins to fully rehydrate and the acidity to infuse into the squash.
- If serving reheated leftovers, verify with an instant-read food thermometer that the internal temperature reaches at least 74°C (165°F).
Storage
Refrigerator: 5 days — Cool within 2 hours of preparation and refrigerate in an airtight glass container at or below 4°C (40°F).
Freezer: 2 months — Store in a freezer-safe container with 1 cm headspace. Squash texture softens slightly upon thawing.
Reheating: Serve chilled, at room temperature, or warm. To reheat, warm in a saucepan over medium-low heat until the internal temperature reaches at least 74°C (165°F).
Troubleshooting
Butternut squash dissolves into mush when folded into the relish
Cause: Squash was cut too small or overcooked during roasting before simmering
Fix: Cannot un-soften the squash; rebrand the mixture as an agrodolce squash spread or crostini topping
Prevention: Ensure squash pieces are cut to a full 1.5 cm and remove from oven when just tender to a fork tip
Relish tastes unpleasantly acidic or overly sharp
Cause: Vinegar was not reduced sufficiently to burn off excess acetic acid vapor, or sugar was under-measured
Fix: Stir in an additional 5 g of granulated sugar and simmer for 2 minutes to restore balance
Prevention: Simmer the vinegar-sugar base until syrupy and large glossy bubbles form before adding the squash
Onions turn bitter and charred during caramelization
Cause: Skillet heat was too high or onions were left unstirred
Fix: Cannot fix burned onions; discard scorched batch and start onion base again to avoid bitter flavor ruin
Prevention: Maintain low to medium-low pan heat and stir frequently, adding small splashes of water if dry
Cultural Context
This relish draws inspiration from Sicilian agrodolce, a sweet-and-sour culinary profile introduced to Southern Italy during Arab rule in the Middle Ages. While classic Sicilian caponata highlights summer eggplant, winter variations across Southern Italy celebrate roasted squashes, plumped dried fruit, briny capers, and vinegar syrups.
