This is my Slow Roast Lamb Sandwich with chimichurrigrilled cheesepickled beetroot, arugula (rocket), caramelised onions, crispy onionsand slow roast pulled lamb. It’s one of my favourite Spring-time sandwiches, so I really hope you enjoy it!

You can totally use lamb slices from the supermarket, but my favourite way to cook lamb is by slow roasting it in the oven for 4hours.
For those of you looking for more sandwich recipes, check out my romesco chicken sandwich which is another great recipe for warmer days, my hot honey chicken sandwich is delicious for a spicier option, for a vegetarian sandwich option, I think you’ll love my eggplant parmesan sandwich!
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About Emily’s Recipe
If you’re new here, hi! I’m Emily – a recipe developer, food content creator, and cookbook author! Thanks for stopping by to check out my Lamb Sandwich recipe. I really hope you enjoy it and please do let me know in the comments if you give it a go!
If you’d like to join a community of food lovers, just subscribe to my newsletter for recipes, cooking tips, and foodie chats. Now, let me tell you a bit more about this recipe…
Texture: the sourdough is lightly toasted, then the filling is soft, meaty, with little bites of crispy onions and fresh arugula (rocket).
Taste: you’ve got the meatiness from the lamb, sweetness from the caramelised onions, spice and freshness from the chimichurri…honestly everything just works so well in this sandwich.
Ease: for those of you who have already made the lamb, this is super easy. You then just have to fry off the onions until caramelised, and make the chimichurri.
Top Tips: 1. get some really good quality bread. 2. fry those onions low and slow for the best caramelised flavour. 3. I actually prefer this lamb sandwich cold.
Would I make this again? yes, it’s perfect for if you’ve got leftover lamb! I’d also make it with other leftover meats too!
Ingredients and Substitutions


Bread: for this recipe, we’re using the most gorgeous Sourdough. I get my sourdough from August bakery in Clapham, London. But get yours from your local bakery! You could also use focaccia!
Mayonnaise: this adds extra moisture and fat to our delicious lamb sandwich. You could alternatively use a light mustard.
Lamb: we’re using my slow roast lamb leftovers here, but you can use sliced supermarket lamb. Or you could use any leftover meats you have in the fridge!
Cheese: cheddar works really well for this recipe, but mozzarella or any melty cheese would be great.
Red onions: we’re using these to then fry down until caramelised. You could use white onions too.
Crispy onions: for a bit of crunch and extra sweetness.
Chemistur: one of my favourite condiments! We’re making this from scratch by combining shallots, garlic, parsley, coriander, dried oregano, chilli, olive oil, red wine vinegar, sugar, salt, and pepper.
Rocket / Arugula: this adds freshness, crunch, and greenery. You can alternatively use lettuce or spinach.
Pickled beetroot: for a pop of colour! You could use grated red cabbage instead!
The full list of ingredients and quantities is at the bottom of this blog in the recipe card!
Step by step instructions with photos


Step 1: Place a frying pan on medium heat and add in a drizzle of olive oil. Follow up with your sliced red onions and fry for 5-10 minutes until slightly softened. Add in the balsamic vinegar, sugar, season with salt and pepper. Then fry for another 5 minutes (stirring frequently) until golden and caramelised.


Step 2: To make the Chimichurri, combine finely chopped shallots, minced garlic, fresh parsley, fresh coriander, fresh red chilli, dried oregano, olive oil, red wine vinegar, sugar, salt, and pepper in a bowl. Taste and season accordingly. Add more chilli if you like things hot!


Step 3: Slice 2 pieces of bread and lightly toast in your toaster.


Step 4: Spread mayonnaise on both slices of bread. On one side, top with caramelised onions, cooked lamb, and slices of cheese. Place under the grill for a few minutes until melted and bubbling. Then, top with chimichurri, crispy onions, rocket/arugula, and pickled beetroot. Top with the second slice of bread and press down.


Step 5: Wrap your lamb sandwich in baking paper, tucking either side underneath the sandwich to seal.

Step 6: Slice your sandwich in half down the middle and open up to see that gorgeous cross section. Enjoy, my friends!
What to do with leftovers
Storage: I would avoid making this sandwich in advance, because the bread soaks up all the juices and can become a bit soggy. I would recommend making all the elements of the lamb sandwich in advance and then assembling the sandwich to order. Store the elements in the fridge for up to 3 days.
FAQs
For sure! Chimichurri goes with an array of cooked meats from beef, chicken, lamb, and pork!
Absolutely! Swap out the mayonnaise for a vegan alternative. Instead of using lamb, you could fry up some pulled mushroom or grated extra firm tofu! Lastly, make sure to use vegan cheese!
No, but if you use gluten-free bread, you’re all good!
More recipes you might enjoy!
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Lamb Sandwich (Out of This World)
This is my Slow Roast Lamb Sandwich with chimichurri, grilled cheese, pickled beetroot, arugula (rocket), caramelised onions, crispy onions, and slow roast pulled lamb.
Instructions
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Place a frying pan on medium heat and add in a drizzle of olive oil. Follow up with your sliced red onions and fry for 5-10 minutes until slightly softened. Add in the balsamic vinegar, sugar, season with salt and pepper. Then fry for another 5 minutes (stirring frequently) until golden and caramelised.
-
To make the Chimichurri, combine finely chopped shallots, garlic, fresh parsley, fresh coriander, fresh red chilli, dried oregano, olive oil, red wine vinegar, sugar, salt, and pepper in a bowl. Taste and season accordingly. Add more chilli if you like things hot!
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Slice 2 pieces of bread and lightly toast in your toaster.
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Spread mayonnaise on both slices of bread. On one side, top with caramelised onions, cooked lamb, slices of cheese. Place under the grill for a few minutes until melted and bubbling. Then top with chimichurri, crispy onions, rocket/arugula, and pickled beetroot. Top with the second slice of bread and press down.
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Wrap your lamb sandwich in baking paper, tucking either side underneath the sandwich to seal.
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Slice your sandwich in half down the middle and open up to see that gorgeous cross section. Enjoy, my friends!
Notes
Storage: I would avoid making this sandwich in advance, because the bread soaks up all the juices and can become a bit soggy. I would recommend making all the elements of the lamb sandwich in advance and then assembling the sandwich to order. Store the elements in the fridge for up to 3 days.
Nutrition
Calories: 880kcalCarbohydrates: 88gProtein: 23gFat: 50gSaturated Fat: 10gPolyunsaturated Fat: 11gMonounsaturated Fat: 26gTrans Fat: 0.03gCholesterol: 29mgSodium: 921mgPotassium: 734mgFiber: 8gSugar: 16gVitamin A: 1561IUVitamin C: 87mgCalcium: 178mgIron: 8mg