Save Succulent barramundi fillets marinated in lemon and garlic hit the grill alongside whole cos lettuce leaves, developing a beautiful char and smoky sweetness. Meanwhile, fresh lemon halves and jalapeños roast until caramelised, their concentrated juices folded into a creamy homemade tartare with capers, dill, and shallots. The result layers perfectly cooked fish, wilted smoky lettuce, and bright spicy condiment between lightly toasted brioche buns.
The first time I made these burgers was during a summer backyard gathering when I wanted something lighter than the usual beef patties but still satisfying. My friends were skeptical about fish on a bun, but one bite changed their minds completely. The smoky grilled lettuce and that spicy tartare sauce turned a simple fish fillet into something extraordinary.
Last summer, my neighbor Sarah dropped by unexpected while I had the grill going. I threw together some barramundi I had marinating, grilled whatever vegetables I could find, and whipped up that spicy tartare. She still texts me asking when Im making those burgers again.
Ingredients
- Barramundi fillets: This Australian beauty has a buttery texture that holds up beautifully on the grill and mild sweetness that pairs perfectly with bold flavors
- Grilled lemon: Charring the lemon halves concentrates their citrus brightness and adds a subtle smoky note that regular lemon juice cannot achieve
- Jalapeños: Grilling tames their heat slightly while adding complexity and that wonderful charred flavor throughout the tartare
- Cos lettuce: Unlike delicate greens, romaine stands up to grilling and becomes sweet and smoky with a satisfying crunch
- Brioche buns: Their slight sweetness and pillowy texture are the perfect vehicle for all these bold flavors without falling apart
Instructions
- Marinate the fish:
- Whisk together olive oil, lemon zest, garlic, salt, and pepper in a shallow dish, then gently coat barramundi fillets and let them sit for 10 minutes while you prep everything else.
- Fire up the grill:
- Get your BBQ or grill pan to medium-high heat with a nice sizzle when you flick water on it.
- Grill the aromatics first:
- Place lemon halves cut-side down and jalapeño halves on the grill, letting them char for 3 to 4 minutes until softened and smoky.
- Make the magic sauce:
- Finely chop those grilled jalapeños, squeeze the charred lemons, then mix with mayo, capers, fresh herbs, shallot, Dijon, and seasoning.
- Cook the barramundi:
- Grill those marinated fillets for about 4 minutes per side until just cooked through with gorgeous char marks and flaky white flesh.
- Char the lettuce:
- Brush those cos leaves with olive oil and give them just 1 to 2 minutes per side until slightly wilted with those perfect grill lines.
- Toast your buns:
- Give your split buns a quick toast on the grill for that extra crunch and warmth.
- Build your masterpiece:
- Slather tartare on both bun halves, then stack with grilled cos lettuce, that beautiful fish, and fresh tomato and cucumber slices.
Save These burgers have become my go-to for summer entertaining because they feel fancy enough for dinner guests but casual enough for a Tuesday night. The combination of hot grilled fish, cool crisp vegetables, and that spicy creamy sauce hits every single craving.
Choosing Your Fish
While barramundi is absolutely perfect here with its buttery flesh and natural sweetness, I have made these with snapper and cod when barramundi was not available. Just make sure whatever firm white fish you choose is fresh and cut into even portions so everything grills at the same rate.
Grilling Lettuce Like a Pro
If you have never grilled lettuce before, you are in for such a treat. The key is using cos or romaine rather than delicate greens and brushing them lightly with oil so they char rather than burn. The transformation from crisp and fresh to sweet and smoky is absolutely worth the extra step.
Make-Ahead Secrets
The tartare sauce actually gets better after a few hours in the fridge, so feel free to make it up to a day ahead. You can also marinate the fish earlier in the day, but do not add the salt until right before grilling or it will draw out too much moisture and affect the texture.
- Keep the grilled lemons and jalapeños warm while prepping the sauce for easier juicing and chopping
- Have all your components ready before you start grilling because everything comes together quickly
- Serve these immediately while the fish is still hot and the lettuce still has that perfect slight crunch
Save These burgers somehow manage to feel elegant and completely indulgent at the same time, exactly the kind of meal that makes grilling season so worth celebrating.
Recipe FAQs
- → What fish works best for these burgers?
-
Barramundi offers firm, flaky flesh that holds up beautifully on the grill. Snapper, cod, or any firm white fish fillet makes an excellent substitute with similar cooking times.
- → How spicy is the jalapeño tartare?
-
Grilling tames the jalapeños' heat while adding subtle smokiness. The sauce delivers gentle warmth rather than overwhelming spice. Leave seeds in or add hot sauce for extra kick.
- → Can I cook this indoors?
-
A grill pan or heavy skillet works perfectly for stovetop cooking. Use high heat to achieve similar char marks on the fish, lettuce, and citrus components.
- → Why grill the lettuce and lemon?
-
Grilling transforms cos lettuce into smoky, slightly wilted leaves that complement the fish. Roasted lemons concentrate their citrus flavour, creating a brighter, more complex tartare sauce.
- → How do I prevent barramundi from sticking?
-
Ensure your grill is well-oiled and preheated to medium-high. Pat fillets dry before marinating, and let them develop a sear before attempting to flip—this creates natural release.
- → What drinks pair well?
-
Crisp Australian Sauvignon Blanc cuts through the rich tartare beautifully. A chilled pale ale or light lager also complements the smoky grilled flavours and zesty condiment.
