Leftover Roast Potato Spanish Tortilla

Turn leftover roast potatoes into this easy Spanish tortilla and serve warm or cold for a simple but delicious lunch or brunch, or pack into a sandwich for the tastiest lunch on the run!

I love to cook a roast dinner at the weekend and then use the leftovers throughout the week for a budget friendly and time saving way of eating. Whilst you have the oven on I find it’s always better to cook more than I need, and then enjoy the leftovers. Leftover roast lamb becomes lamb wraps or shepherd’s pie, and leftover roast chicken can be turned into a leftover chicken curry or chicken salad. The same goes with the sides – I love making cheese and onion rolls with leftover mashed potato, so I thought I’d turn my attention to roast potatoes. True, they’re not always the side dish left at the table, but if you are like me, you can over cater. Or if I’ve a couple of potatoes left in the bag I’ll cook extra as I know I can use them up.

Why we love this recipe

• This recipe for leftover roast potatoes is so simple and uses 6 store cupboard staple ingredients.
• Budget friendly – using basic ingredients like eggs, onions and potatoes, this easy dish is one of those budget recipes that really doesn’t taste ‘budget’.
• A traditional Spanish tortilla (Spanish omelette) is made from potatoes fried in oil, so by using leftover roast potatoes you get that fried potato taste in the tortilla, which also adds extra flavour.
• A potato omelette is great for lunches and lunchboxes as it can be enjoyed cold.

Ingredients notes and substitutions

• Roast potatoes – any leftover potatoes will do, crispy or not so crispy! Although I recommend not using super crispy to the point of being burnt roasties in this omelette.
• Eggs – size large.
• Onion – optional in traditional Spanish tortilla, however I have always eaten with with onions in Spain, and love the flavour it gives to the dish. You can use white or brown onion, a red onion, or 2-3 spring onions / scallions
• Salt – salt is important in this recipe! It really brings out the flavour of both the potatoes and eggs. If you’ve heavily salted your roast potatoes then keep this in mind when you salt the eggs.
• Oil – I like to use olive oil, but you can use canola oil or vegetable oil if you prefer.

How to make this recipe

For the full detailed recipe please scroll down to the recipe card at the end of the post.

1. Slice the onions into half-moon shapes and fry in olive oil over a low heat until soft and starting to caramelise, stirring every so often to prevent them from catching. Remove from the heat and leave to cool.
2. Slice the leftover roast potatoes.

3. Whisk the eggs in a large mixing bowl and add a pinch of salt. Stir in the sliced potatoes and cooked onions.
4. Wipe the frying pan with a piece of kitchen paper towel then add the other ½ tablespoon of olive oil ad pour the egg and potato mixture in to the pan.
5. Cook over a low-medium heat for 6-8 minutes.

6. Once the edges become firm, use a spatula to ease it gently away from the edge of the pan then place a plate over the frying pan (use a plate that is larger than the frying pan).
7. Carefully tip the frying pan over so the tortilla tips out on to the plate, cooked side up.

8. Carefully slide the tortilla back in to the pan, raw side down.

9. Cook the other side for 3-4 minutes until cooked all the way through.
10. You can serve the tortilla warm or cold. Store any leftovers in the fridge.

FAQ

My recipe tips

• Don’t use too many potatoes otherwise the tortilla can become dry. If you have an abundance of leftover roast potatoes then either make two potato omelets, or turn them into patatas bravas by reheating them in the oven at 180˚C / 360˚F and serving with bravas sauce.
• To turn the tortilla espanola over, once the egg is cooked at the edges, place a plate that is slightly larger than your frying pan over the top of the pan and carefully using a tea towel, quickly flip the pan over so the tortilla is on the plate. Place the pan down then carefully slide the tortilla back in to the pan, uncooked side down. There will be a little raw egg on the plate.
• You have to be confident when you flip the tortilla! Doing it quickly and firmly means the tortilla is less likely to break.
• Heat – don’t be tempted to cook the potato omelette over too high a heat as it can become rubbery.

Storage

The cooked ommelete will keep in the fridge, covered, for up to 2 days.

Serving Ideas

• With a salad like this rocket salad, or pear and walnut salad.
• In a sandwich with mayonnaise and lettuce – my absolute favourite!
• As part of a Spanish tapa with garlic mushrooms, patatas bravas, and Spanish orange and pomegranate salad.

Variations

• Vegetables – add leftover cooked carrots, parsnips, making sure the weight is the same or near to the one given below for the potatoes.
• Meat – add a little leftover ham, cooked sausage or cooked bacon. Chop it finely to ensure it heats through properly.
• Herbs – 2 tablespoons of fresh herbs such as chives, parsley or basil would be delicious. Whisk them into the beaten eggs before adding the potatoes.

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