Equipment
Ingredients
Sardines
- 4 sardines, cleaned, heads removed
- 12 g flour
- 2 g salt, flaked
- 1 g black pepper, freshly ground
Pickled Red Onion
- 45 ml olive oil
- 1 red onion, sliced
- 20 g sugar
- 30 ml red wine vinegar
- 15 ml capers, drained
- 3 g parsley, chopped
Assembly
- 4 sourdough bread
- 50 g unsalted butter, softened
- 10 g wholegrain mustard
- 1 tomato, finely sliced
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 568 kcal
- Protein
- 29 g
- Carbohydrates
- 38 g
- Fat
- 33 g
- Fiber
- 2 g
- Sugar
- 10 g
- Sodium
- 972 mg
- Saturated Fat
- 8 g
- Trans Fat
- 0 g
- Monounsaturated Fat
- 11 g
- Polyunsaturated Fat
- 2 g
- Cholesterol
- 27 mg
- Potassium
- 554 mg
- Calcium
- 228 mg
- Iron
- 4.4 mg
- Magnesium
- 98 mg
- Phosphorus
- 417 mg
- Zinc
- 3.1 mg
- Vitamin A
- 159 mcg
- Vitamin C
- 8 mg
- Vitamin E
- 2.2 mg
- Vitamin K
- 24 mcg
- Vitamin B6
- 0.1 mg
- Vitamin B12
- 0.0 mcg
- Thiamin
- 0.42 mg
- Riboflavin
- 0.26 mg
- Niacin
- 2.9 mg
- Folate
- 81 mcg
- Water
- 94 g
Sources: Aggregated Public Data, USDA FoodData Central
Method
Using a sharp knife, slice the underside of each sardine from the belly opening toward the tail to butterfly the fish. Trim the tail and fins with scissors.
Place the sardines skin-side up on a flat surface. Press firmly along the backbone with your fingers to flatten the fish.
Turn the fish over. Lift the spine away from the meat and pull it out, removing any small bones. Inspect the flesh and remove any remaining bones.
Mix the flour, salt, and black pepper on a shallow plate. Coat each sardine in the flour and shake off the excess.
Heat 15ml of olive oil in a saucepan over medium heat. Add the sliced onion and cook for 5 minutes until soft. Stir in the sugar, vinegar, and capers for 30 seconds. Remove from heat and stir in parsley.
Heat the remaining 30ml of olive oil in a frying pan over medium-high heat. Fry the sardines for 1 minute per side until the internal temperature reaches 74°C/165°F.
Toast the sourdough bread. Combine the softened butter and mustard, then spread onto the toast. Layer with tomato slices, one sardine, and the warm onion mixture.
Chef's Notes
- When butterflying sardines, ensure your knife is extremely sharp to make clean cuts and avoid tearing the delicate flesh. Pressing down firmly on the backbone helps to make them lie flat for even cooking.
- Don't overcrowd the pan when frying the sardines. Cook them in batches if necessary to ensure they get crispy and don't steam, which can result in a less desirable texture.
- The pickled red onions can be made a day in advance to allow the flavors to meld beautifully. They add a crucial sweet and tangy counterpoint to the richness of the sardines.
- For an extra layer of flavor, you can lightly grill or toast the sourdough bread before buttering it. This adds a smoky note that complements the fish.
- Taste and adjust the seasoning of the pickled onions and the sardine dredge. The saltiness of capers and sardines can vary, so a little tasting as you go is always recommended.
Storage
Troubleshooting
Sardine flesh tears while deboning
Cause: Applying too much pressure or using a dull knife
Fix: The fish will still be edible; press the flesh back together before dredging in flour to help bind it
Prevention: Use a very sharp knife tip to loosen the spine and work slowly with light pressure
Sardines are soggy rather than crisp
Cause: Pan was not hot enough or too many fish were added at once
Fix: Cannot be fixed once cooked
Prevention: Ensure oil is shimmering before adding fish and do not crowd the pan
Cultural Context
Sardines are a staple in Mediterranean coastal cuisines, particularly in Spain, Portugal, and Italy, where they are a readily available and affordable source of protein. This dish, with its fresh ingredients and simple preparation, reflects the healthy and vibrant culinary traditions of the region, often enjoyed as a light meal or appetizer during warmer months.
