Smoked Mackerel and Pickled Onion Tart

By AislePrompt Editorial · Published 2026-04-21 · Updated 2026-04-21

A delicate tart featuring smoked mackerel and sharp pickled onions atop a crisp pastry base, perfect for a light supper. This Mediterranean-inspired one-pot recipe, ready in about 67 minutes, layers pastry dough, mackerel fillets, red onion into a dessert worth slowing down for — great for weekend baking, holiday tables, or any time you want a sweet payoff at the end of a meal. Each serving lands at about 480 calories and feeds 4, so it slots into a weekend bake or a special-occasion dessert tray. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Ingredients

• 225g pastry dough
• 200g mackerel fillets
• 1 small red onion
• 60ml white wine vinegar
• 10g granulated sugar
• 2 tbsp fresh dill
• 120ml heavy cream
• 1 tsp lemon zest
• 5g salt
• 2g black pepper

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Instructions

1. Step 1: Preheat oven to 180°C. Roll out pastry dough into a 28cm circle, transfer to a baking sheet, and prick with a fork. Bake for 12 minutes until golden, then let cool.
2. Step 2: Thinly slice red onion and marinate in white wine vinegar, sugar, and 2g salt for 20 minutes until translucent. Drain and pat dry.
3. Step 3: Flake smoked mackerel into small pieces, discarding skin and bones. Combine with 120ml heavy cream, lemon zest, 1g salt, and 2g black pepper, mixing until smooth.
4. Step 4: Spread mackerel mixture evenly over cooled pastry base. Top with drained pickled onions and sprinkle with fresh dill. Bake for 15 minutes until edges are golden.