Hamdi Saidani This Next-level steak & onion sandwich is a juicy and caramelized recipe, which is made with tender flank steak and sweet onions. It’s a restaurant-quality dish, ready in about an hour.
Next-level Steak & Onion Sandwich Ingredients
- 400g flank skirt steak or bavette
- 2 large onions
- 20g unsalted butter
- olive oil
- 70g dark brown sugar
- 125ml red wine vinegar
- 1 ciabatta loaf
- extra virgin olive oil
- optional: English mustard
- 1 handful of watercress
How To Make a Next-level Steak & Onion Sandwich
- Prep the steak and onions: Remove the steak from the fridge to let it come to room temperature. Cover it with greaseproof paper and bash it with the base of a heavy pan to tenderize it. Peel the onions and slice them into 2cm-thick rounds.
- Caramelize the onions: In a large non-stick frying pan, melt the butter with a lug of olive oil and the sugar over a medium heat. Place the onion rounds in a single layer and cook for 5 minutes. Pour in the vinegar, cover with a lid, reduce the heat to low, and cook for around 35 minutes until beautifully golden and caramelized.
- Cook the steak: While the onions cook, season the steak all over with sea salt and black pepper. Place a large, heavy-bottomed pan on a high heat. Once screaming hot, drizzle the steak with olive oil and cook for 3 minutes on each side for medium, or to your liking.
- Rest and slice: Remove the cooked steak to a plate and let it rest for at least 1 minute. Slice it into 1cm thick strips and toss them in their own resting juices with a drizzle of extra virgin olive oil.
- Assemble the sandwich: Cut the warm ciabatta loaf in half horizontally. Rub the inside of each piece in the steak resting juices. Spread with mustard, if using, then layer with the caramelized onions, the sliced steak, and a few pinches of watercress. Place the other piece of bread on top, press down lightly, and serve.
Recipe Tips
- How to get the most tender steak? Bashing the steak with a heavy pan, as the recipe directs, helps to break down the muscle fibers and tenderize it. Slicing it against the grain after it has rested is also a crucial step.
- How to get perfectly caramelized onions? The key is low and slow heat. Don’t be tempted to rush this step. Cooking the onions gently for the full 35 minutes allows their natural sugars to release and caramelize, creating a deep, sweet flavor.
- Can I use a different cut of steak? Yes. If you can’t find flank or skirt steak, a good quality sirloin or rump steak would also be delicious.
- Can I make the onions ahead of time? Absolutely. Caramelized onions store very well. You can make them up to 3 days in advance and keep them in an airtight container in the refrigerator. Just reheat them gently before assembling the sandwich.
What To Serve With a Steak & Onion Sandwich
This hearty sandwich is a complete meal, but it pairs wonderfully with classic sides.
- Crispy french fries or potato wedges
- A simple green salad with a sharp vinaigrette
- A few dill pickles on the side
- A creamy coleslaw
How To Store a Steak & Onion Sandwich
- Refrigerate: This sandwich is best enjoyed immediately while the steak and bread are warm. If you have leftovers, it’s best to store the cooked steak and the caramelized onions in separate airtight containers in the refrigerator for up to 2 days.
Steak & Onion Sandwich Nutrition Facts
- Serving Size: 1 sandwich
- Calories: 750 kcal
- Fat: 35g
- Carbohydrates: 65g
- Protein: 40g
Nutrition information is estimated and may vary based on ingredients and cooking methods used.
FAQs
Why remove the first layer of the onion?
The outermost layer of an onion’s flesh, just under the papery skin, can sometimes be a bit tough or dry. Removing it ensures that all the onion slices in your sandwich are perfectly soft and tender.
Do I have to use ciabatta bread?
No, but a sturdy, crusty bread is best to hold up to the juicy steak and onions without getting soggy. A good quality baguette or sourdough would also be excellent choices.
Is this sandwich very sweet?
It has a wonderful balance of flavors. The deep sweetness of the long-cooked caramelized onions is perfectly balanced by the savory, well-seasoned steak and the peppery bite of the fresh watercress.
Try More Recipes:
- The ultimate steak & roasties Recipe
- Gary Barlow’s Scrumptious Steak & Stout Pies Recipe
- Grilled Steak Ratatouille & Saffron Rice Recipe
Next-level Steak & Onion Sandwich Recipe
Course: DinnerCuisine: BritishDifficulty: Easy4
15
minutes45
750
kcalA tender, juicy steak sandwich is taken to the next level with slow-cooked, deeply sweet caramelized onions, all piled onto a warm ciabatta loaf.
Ingredients
400g flank or skirt steak
2 large onions
20g unsalted butter
70g dark brown sugar
125ml red wine vinegar
1 ciabatta loaf
Olive oil & extra virgin olive oil
Optional: English mustard
1 handful of watercress
Directions
- Tenderize the steak by bashing it with a heavy pan.
- Slowly cook the sliced onions in a pan with butter, oil, and sugar for 5 minutes. Add the vinegar, cover, and cook on low for 35 minutes until caramelized.
- Warm the ciabatta in a low oven.
- Cook the seasoned steak in a very hot pan for 3 minutes per side for medium.
- Rest the steak for a minute, then slice it and toss with its juices.
- Assemble the sandwich by layering the warm ciabatta with the steak resting juices, mustard (if using), caramelized onions, sliced steak, and watercress.
Notes
- Allowing the steak to come to room temperature before cooking is crucial for an even cook.
- Don’t skip resting the steak after cooking; it’s essential for a juicy result.
- The low-and-slow cooking of the onions is the secret to their incredible flavor.
- This is a “principal recipe” that can be easily adapted with different cuts of steak or types of bread.