This is a ground beef and potato bake with a savoury mustard-spiked filling, topped with overlapping sliced potatoes and melted cheddar instead of the usual mash. It takes about an hour start to finish and feeds four people well. The Dijon and smoked bacon do real work here — the filling tastes like it cooked longer than it did.
Smart swaps
- Smoked streaky bacon works just as well as pancetta — same fat content, same smoky hit. Regular unsmoked bacon is a weaker substitute; add a small pinch of smoked paprika if that’s all you have.
- Passata is just sieved tomatoes. A spoonful of tomato paste thinned with a little water does the same job in a pinch.
- Dijon mustard is worth buying if you don’t have it — wholegrain mustard is a reasonable swap but gives a slightly coarser texture in the sauce. Yellow mustard is too sharp and sweet; skip it.
- Cheddar can be swapped for any hard cheese that melts well, like Gruyère or Colby.
Why this recipe works
Two things matter most here. First, browning the beef properly before adding any liquid — this means cooking it in a hot, dry pan without stirring too early, letting the moisture evaporate so the meat colours rather than steams. Grey, steamed mince has almost no flavour; browned mince does. Second, the sliced potato topping needs to be part-boiled before it goes on top. Raw potato slices won’t cook through fully in 30 minutes at oven heat, especially under a layer of cheese. The five-minute par-boil and the cold-water stop are what give you a topping that’s tender inside and crisp on the surface once baked.
What can go wrong
- Watery filling: If the sauce hasn’t reduced enough before going into the baking dish, the finished pie will be soupy. After the 15-minute simmer, the mixture should look thick and glossy, not brothy. Give it another few minutes uncovered if needed.
- Potato slices falling apart: Over-boiling during the par-cook is the usual cause. Five minutes is enough — they should still hold their shape when you lift one. Drain them gently and cool them quickly under cold running water so they firm back up.
- Undercooked beef: Ground beef must reach an internal temperature of 160°F (71°C). If you’re unsure, use an instant-read thermometer in the centre of the filling before serving — don’t rely on colour alone.
- Cheese burning before potatoes are done: If the top is browning too fast in the last 10 minutes, lay a loose sheet of foil over the dish. Remove it for the final 5 minutes to crisp back up.
- Bland filling: Beef stock varies a lot in saltiness depending on the brand. Taste the filling before it goes into the dish and adjust — this is the only real chance to season it properly.
Keeping and reheating
Cool the pie completely before covering it — trapping steam makes the potato topping go soft. Refrigerate leftovers within two hours and eat within three days. To reheat, cover the dish with foil and warm in a 350°F (175°C) oven for 20–25 minutes until the filling is piping hot throughout; skip the microwave if you want the potato topping to stay firm rather than soggy. This pie also freezes well: portion it into airtight containers once cold and freeze for up to two months. Thaw overnight in the fridge before reheating — do not reheat from frozen, as the centre won’t reach a safe temperature before the top overcooks.
Beef & Mustard Cottage Pie with Sliced Potato Top
Equipment
Ingredients
1.1 lb ground beef (minced beef) - 500g, lean minced beef, 5% fat or less- 6 rashers smoked streaky bacon - chopped, approximately 180g / 6oz
1 tablespoon olive oil - for frying
1 medium onion - finely diced
2 large carrots - peeled and grated, approximately 200g / 7oz
1 clove garlic - crushed or finely minced
2 cups beef stock - 500ml, beef broth
⅓ cup passata or crushed tomatoes (tomato puree with seeds removed) - 80ml, sieved tomatoes
1 tablespoon Dijon mustard
3 large potatoes - approximately 750g / 1.6lb total, such as Maris Piper or Yukon Gold- 3.5 oz mature cheddar cheese - grated, 100g / 1 cup loosely packed
1 pinch ground black pepper - to taste ; freshly ground
Instructions
- Finely dice the onion, peel and grate the carrots, crush or finely mince the garlic, and chop the bacon. Set aside, ready to be cooked.1 medium onion, 2 large carrots, 1 clove garlic, 6 rashers smoked streaky bacon
- Heat a large dry frying pan over high heat. Add the ground beef and spread it out in an even layer. Let it cook undisturbed for 2–3 minutes until the underside is well browned, then break it up into fine pieces with a wooden spoon. Continue cooking, stirring occasionally, until no pink remains and the meat is deeply browned — about 5–6 minutes total. Transfer to a bowl and set aside.1.1 lb ground beef (minced beef)
- Reduce the heat to medium. Add 1 tablespoon of olive oil to the same pan. Add the chopped bacon and cook for 2–3 minutes until the fat renders and the edges start to crisp. Add the diced onion and grated carrots, and cook for a further 3–4 minutes until softened. Stir in the crushed garlic and cook for 30 seconds until fragrant. Return the browned beef to the pan and stir to combine.1 tablespoon olive oil, 6 rashers smoked streaky bacon, 1 medium onion, 2 large carrots, 1 clove garlic, 1.1 lb ground beef (minced beef)
- Pour in the beef stock and passata, then stir in the Dijon mustard. Bring to a boil, stirring occasionally.2 cups beef stock, 1/3 cup passata or crushed tomatoes (tomato puree with seeds removed), 1 tablespoon Dijon mustard
- Reduce the heat to low and let the filling simmer for 15 minutes with the lid on, stirring once or twice.
- Meanwhile, preheat the oven to 400°F / 200°C (180°C fan-forced / Gas Mark 6).
- Peel the potatoes and slice them about 3–4mm (⅛ inch) thick — roughly the thickness of a pound coin. Par-boil in a saucepan of salted boiling water for 5 minutes, then drain in a colander and cool under cold running water to stop the cooking. Drain well.3 large potatoes
- Spoon the filling into an oven-safe baking dish (approximately 9×9 inch / 23x23cm, 2 inches deep) and spread it out evenly. Arrange half the potato slices in an overlapping layer on top. Scatter over half the grated cheddar. Add a second overlapping layer of the remaining potato slices, then top with the rest of the cheddar. Drizzle lightly with olive oil and season with freshly ground black pepper.3 large potatoes, 3.5 oz mature cheddar cheese, 1 tablespoon olive oil, 1 pinch ground black pepper
- Bake at 400°F / 200°C (180°C fan-forced / Gas Mark 6) for 25–30 minutes until the cheese is bubbling and the potato edges are golden and crisp. Let the pie rest for 5 minutes before serving.
Notes
Nutrition
Your questions, answered
Do I need to cook the bacon separately before adding it to the filling?
No — the recipe has you cook the onion and carrots in the same pan after browning the beef, and the bacon fat renders into the base as part of that process. Just make sure the bacon pieces get some direct pan contact so they don’t stay rubbery; a couple of minutes on medium heat is enough before you add the beef back in.
How thin do the potato slices need to be, and do I need a mandoline?
About 1mm thick is the target — roughly the thickness of a pound coin. You don’t need a mandoline; a sharp knife and a steady hand work fine. Uneven slices just mean some pieces will be slightly more tender than others, which isn’t a problem.
My ground beef is clumping into big chunks. How do I get a fine mince texture?
Break it up with a wooden spoon or spatula as soon as it hits the hot pan, before it has a chance to set into large pieces. Keep pressing and separating it as it cooks — working it constantly for the first two minutes gives you a fine, even texture throughout the filling.
Can I assemble this ahead of time and bake it later?
Yes — assemble the whole dish, cover it tightly, and refrigerate for up to 24 hours before baking. Add an extra 5–10 minutes to the bake time since it’s going in cold, and check that the filling is bubbling at the edges before you pull it out.
How do I know when the pie is actually done in the oven?
The top should be deep golden brown and you should see the filling bubbling around the edges of the dish. If you want to be certain, insert a knife into the centre and hold it there for five seconds — it should feel hot when you touch it to your wrist. An instant-read thermometer reading of 160°F (71°C) in the filling is the definitive check.
If you liked this one
- Savory British Beef Pies
- Hearty Beef Cauliflower Bake
- Anglo-Indian Curry Pie
- Cumberland Sausage Mince Pie
