Looking for a sandwich that’s hearty, flavour-packed, and perfect for any time of the day? This Roast Beef and Balsamic Onions Sandwich is a true showstopper. Combining tender roast beef, caramelised balsamic onions, and creamy mozzarella, this sandwich is layered with rich, savoury flavours and balanced with the freshness of rocket leaves. It’s easy to make and guaranteed to impress whether you’re serving it for lunch, dinner, or a special occasion
Why You’ll Love This Sandwich:
- Gourmet Flavours at Home: The combination of sweet balsamic onions, savoury roast beef, and creamy mozzarella tastes like something you’d find at a high-end café.
- Customisable: Use your favourite bread, swap the mozzarella for cheddar, or add a touch of spice with a drizzle of sriracha.
- Perfect for Any Occasion: Whether it’s a hearty lunch, a light dinner, or a crowd-pleasing party snack, this sandwich fits the bill
- .Quick and Easy: Despite its gourmet appeal, this recipe is simple and comes together in less than 30 minutes.
Tips for Making the Perfect Roast Beef and Balsamic Onions Sandwich:
- Bread Matters: Choose a sturdy bread like sourdough, ciabatta, or a baguette to hold up to the fillings without becoming soggy.
- Cheese Melting Tip: For perfectly melted cheese, cover the pan with a lid while cooking the sandwich.
- Make Ahead: Prepare the balsamic onions ahead of time and store them in the fridge for up to 3 days to save time.
- Roast Beef Options: Use deli-style roast beef or leftover roast from Sunday dinner for a more rustic feel.
- Customise the Veggies: Add grilled courgettes, aubergines, or sun-dried tomatoes for extra depth of flavour.
Frequently Asked Questions:
Can I use another type of cheese?
bsolutely! Cheddar, provolone, or even brie would work beautifully in this recipe.
How do I keep the sandwich from getting soggy?
Ensure your onions are well caramelised and not overly wet. Also, spread the mayo and mustard evenly to create a moisture barrier.
Can I make this sandwich vegetarian?
Yes! Replace the roast beef with roasted portobello mushrooms or grilled aubergine slices for a vegetarian version.
How do I store leftovers?
It’s best to eat the sandwich fresh, but if you have leftovers, wrap them in foil and reheat in the oven for a crisp finish.
Roast Beef and Balsamic Onions Sandwich
Course: Dinner, LunchDifficulty: Easy2
servings10
minutes20
minutes30
minutesIngredients
- For the Filling:
200g sliced roast beef
150g mozzarella cheese
2 tbsp light mayo
1 tbsp Dijon mustard
1 jar roasted peppers
Handful of rocket leaves
Salt and pepper, to taste
Butter or mayonnaise (for spreading outside the bread)
- For the Sweet Balsamic Onions:
2 red onions, thinly sliced
2 tbsp brown sugar
2 tbsp balsamic vinegar
2 tbsp water
½ tsp salt
1 tbsp olive oil
Directions
- Prepare the Sweet Balsamic Onions:
- Heat the olive oil in a pan over medium heat. Add the sliced onions and sauté for about 5 minutes until softened.
- Stir in the brown sugar, balsamic vinegar, water, and salt. Reduce the heat to low and simmer, stirring occasionally, for 15–20 minutes until the onions are caramelised and the liquid has reduced. Remove from heat and set aside.
- Mix the Sauce:
- In a small bowl, mix the mayonnaise and Dijon mustard until smooth.
- Assemble the Sandwich:
- Slice your bread into four slices. Spread the mayo-mustard mixture evenly on two slices.
- Layer on the sliced roast beef, followed by the caramelised balsamic onions.
- Add the roasted red peppers, mozzarella cheese, and rocket leaves. Top with the remaining slices of bread.
- Cook the Sandwich:
- Heat a large frying pan or griddle over medium heat. Spread butter or mayonnaise on the outside of the sandwich for a golden, crispy finish.
- Place the sandwich in the pan and cook for about 4 minutes per side, pressing down gently with a spatula for even browning. Flip carefully to ensure the fillings stay intact.
- Serve:
- Once the bread is golden and crispy and the cheese has melted, remove the sandwich from the pan. Slice in half and serve immediately.