Potato and Onion Frittata
A simple, comforting frittata with potatoes, onions and cheese.
Allergens: contains eggs, milk. Brands differ, so always check the labels on what you buy.
Per serving (approx.): 25g carbs · 2g sugars · 3g fibre. Estimates for carb counting, not medical advice. If you have diabetes, follow your GP or dietitian's advice.
Not every ingredient has a checked price at Asda, Sainsbury's, Aldi, Co-op, Iceland, so they aren't compared here yet (more are checked every day). Lidl doesn't publish prices online, so it can't be compared.
Ingredients and prices
Swipe the table to see every supermarket.
| Ingredient | Tesco | Morrisons |
|---|---|---|
| Potatoespack 2kg · use 200g | £1.56£0.08 per 100g | £1.85£0.09 per 100g |
| Onionpack 1kg · use 100g | £0.95£0.10 per 100g | £0.95£0.10 per 100g |
| Eggspack 6 pack · use 2 | £1.80£0.30 each | £1.80£0.30 each |
| Unsalted butterpack 250g · use 50g | £1.85£0.74 per 100g | £1.85£0.74 per 100g |
| Semi skimmed milkuse 50ml | £0.85568ml · £0.15 per 100ml | £0.85568ml · £0.15 per 100ml |
| Grated Cheesepack 200g · use 50g | £2.50£1.00 per 100g | £1.89£0.76 per 100g |
| Basket total (full packs) | £9.51 | £9.19 |
| Cost of what this recipe uses | £1.80 | £1.71 |
| Per serving | £0.45 | £0.43 |
From your cupboard
Not in the prices above. Check you have these before you start.
Prices checked on 5 October 2026 from each supermarket's own listing or a price-comparison site. Each shop's unit price (or pack size) is shown under its price, and "cost of what this recipe uses" compares like with like (tap a price to see its source). Cheapest in each row is ticked. Prices, offers and pack sizes change; loyalty-card prices are not included unless stated.
Method
The method is written for 4. For a different number, use the amounts in the table above.
- Prepare the vegetables by peeling the 200g of potatoes into 1cm cubes and finely dicing the 100g onion. Ensure the potatoes are cut small so they cook quickly within the time limit.
- Melt the 50g unsalted butter in a 20cm non-stick frying pan over medium heat. Add the potato cubes and fry for 8 to 10 minutes, stirring occasionally, until they are tender when pierced with a fork.
- Add the diced onion to the pan with the potatoes. Continue to cook over medium heat for another 4 to 5 minutes until the onions are translucent and starting to turn lightly golden brown.
- While the vegetables fry, crack the 2 eggs into a large bowl and add the 50ml semi-skimmed milk. Whisk vigorously with a fork, adding a pinch of salt and black pepper until the mixture is completely smooth and frothy.
- Pour the egg mixture over the potatoes and onions in the pan. Use a spatula to ensure the vegetables are spread evenly in a single layer and turn the heat down to low.
- Sprinkle the 50g of grated cheese over the top of the egg mixture. Cover the pan with a tight-fitting lid and cook for 5 minutes or until the eggs are set at the edges and no longer wobble when shaken.
- Slide the frittata from the pan onto a warm plate, or serve it directly from the pan. Slice into 4 wedges and serve while warm, ensuring the cheese is melted and stretchy.
Tips
- To make this cheaper, use any leftover hard cheese or swap the potatoes for a tin of drained canned chickpeas.
- To batch-cook, cool the frittata completely before wrapping in foil for the fridge; eat up to 2 days.
- To reheat safely, microwave slices for 60-90 seconds until steaming hot throughout; reheat only once.
Nothing wasted: your leftover ingredients
Supermarkets sell set pack sizes, so you'll have some ingredients left. Here's how to keep them, and other recipes here that use them up.
- Potatoes · about 1.8kg left
Keep somewhere cool and dark (not the fridge). Use extras for mash, wedges or a traybake later in the week. Use it in: One-pan chicken, potatoes and veg, Beef & Veggie Skillet, Chicken and Sweet Potato Tray Bake. - Onion · about 900g left
Chop the rest and freeze it flat in a bag: it cooks straight from frozen in soups, curries and sauces. Whole onions keep for weeks somewhere cool, dark and dry. Use it in: Chilli con carne, Egg fried rice, Creamy Tomato & Hidden Veg Pasta Bake. - Unsalted butter · about 200g left
Check the label: most raw ingredients can be frozen before their use-by date, and cupboard staples keep for months. Use it in: Banana muffins, Ginger Cake, Pad Thai with Chicken. - Semi skimmed milk · about 950ml left
Keep in the fridge and use by the date on the pack; milk can also be frozen. Use it in: Rich Chocolate Mousse, Beef and Ale Pie, Banana muffins. - Grated Cheese · about 150g left
Keep wrapped in the fridge. Grate any extra and freeze it: it melts straight from frozen on pasta bakes and toasties. Use it in: Creamy Tomato & Hidden Veg Pasta Bake, Tuna and Sweetcorn Pasta Bake, Cheesy Bean & Rice Casserole.
Storing leftovers
Cool leftovers and put them in the fridge or freezer within 1–2 hours. Eat fridge leftovers within 2 days, or freeze them. Defrost in the fridge and reheat only once, until steaming hot all the way through (Food Standards Agency guidance).