Slow-Roasted Barramundi with Lemon Myrtle and Roasted Wattleseed Sauce

By , Test Kitchen Director · Reviewed by AislePrompt Editorial · ·

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A delicate barramundi fillet slow-roasted and served with a creamy sauce infused with native lemon myrtle and roasted wattleseed for a uniquely Australian flavor. This Australian-inspired seafood recipe, ready in about 30 minutes, pairs barramundi fillets, salt, black pepper for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 310 calories and feeds 4, so it slots cleanly into a weekly meal plan and pairs well with a quick salad or grain on the side. 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.

Prep: 10 min Cook: 20 min Serves 4 Australian cuisine 310 cal/serving
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Ingredients

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Instructions

  1. Step 1: Preheat the oven to 275°F (135°C). Pat dry 4 barramundi fillets and season them evenly with 1 tsp salt and 1/2 tsp black pepper.
  2. Step 2: Heat 2 tbsp olive oil in a large oven-safe skillet over medium heat. Place fillets skin-side down and sear for 2 minutes until golden but not fully cooked.
  3. Step 3: Transfer the skillet with fillets to the preheated oven and roast gently for 12-15 minutes until the fish flakes easily with a fork.
  4. Step 4: While the fish roasts, combine 1/2 cup heavy cream, 1 tbsp ground roasted wattleseed, 1 tsp lemon myrtle powder, 2 tbsp fresh lemon juice, and 2 tbsp unsalted butter in a small saucepan over low heat. Stir continuously until the sauce thickens slightly and the flavors meld, about 5 minutes.
  5. Step 5: Remove the fish from the oven, spoon the warm sauce generously over each fillet, and garnish with 2 tbsp chopped fresh parsley before serving.

Frequently asked questions

How long does Slow-Roasted Barramundi with Lemon Myrtle and Roasted Wattleseed Sauce take to make?

Total time is about 30 minutes (10 min prep + 20 min cook). Most home cooks find this fits comfortably into a weeknight; double the batch on Sunday for two dinners.

How do I store leftover Slow-Roasted Barramundi with Lemon Myrtle and Roasted Wattleseed Sauce?

Refrigerate in a covered airtight container for up to 3–4 days (FDA FoodKeeper guideline for cooked fish). Store any fresh salsa or citrus-based garnish in a separate container — it keeps for up to 2 days. Freeze cooked fish (without fresh garnishes) for up to 3 months; thaw overnight in the fridge and reheat gently at 275°F until just warmed through to preserve texture.

Can I substitute ingredients in Slow-Roasted Barramundi with Lemon Myrtle and Roasted Wattleseed Sauce?

Yes — most ingredients in this recipe have flexible swaps. For oil, use any neutral high-smoke-point oil (avocado, grapeseed, refined coconut). For aromatics, dried herbs at ⅓ the volume of fresh work in a pinch. The full ingredient list is shoppable on Instacart so you can see substitutes in real time.

How do I scale Slow-Roasted Barramundi with Lemon Myrtle and Roasted Wattleseed Sauce for a different number of people?

The recipe is written for 4 servings. Multiply each ingredient by (your serving target / 4). Cook time stays roughly the same up to 2x; for 3-4x batches, switch from a skillet to a sheet pan or stockpot so the food isn't crowded — overcrowding steams instead of browns.

What goes well with Slow-Roasted Barramundi with Lemon Myrtle and Roasted Wattleseed Sauce?

Australian seafood like this pair well with a simple grain (rice, couscous, or crusty bread), a quick salad with acid (lemon vinaigrette, pickled onions), and a pan sauce or yogurt-based dip. Tap "Plan a meal with the AI" to get specific side suggestions.

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