Is Your Shepherd’s Pie Runny? This Is Probably Why…

How to thicken a runny Shepherd's Pie

Shepherd’s Pie is one of the best and most traditional British dishes. But it’s pointless making one if it’s going to turn out to be a sloppy, runny mess.

That’s why we’re about give you a top-notch Shepherd’s Pie recipe, but first, some crucial tips on how to avoid making it a runny disaster.

Why Is Your Shepherd’s Pie Runny? 

Your Shepherd’s Pie might turn out to be runny for a few reasons: 

  • If you use low quality lamb mince (which may contain added water)
  • If you use too much stock
  • If you don’t reduce/simmer for long enough
  • If you don’t use (enough) tomato purée
  • If your mashed potato topping is sloppy

So how do you prevent / fix all of that and thicken your Shepherd’s Pie?

Here’s how…

How To Thicken Shepherd’s Pie

Before anything, we should say that whilst there are differences between a Shepherd’s Pie and Cottage Pie, the same principles apply when it comes to thickening both dishes.

In an ideal world, you won’t need to salvage your Shepherd’s Pie. You’ll just use good quality lamb mince (ideally from the butcher’s) along with suitable quantities of the other ingredients, which should give you a great end result. 

But if you do find yourself in the position where you need to thicken a runny looking Shepherd’s Pie, there’s a few things you can do:

  • Use plain, all-purpose flour (but this needs to be done at the right stage of the cooking process – see below).
  • Use cornflour and water (again, see below for when to add).
  • Alternatively, it may just be a case of straining some of the liquid away, or simmering for a bit longer. 
  • Ensure your potatoes are drained of water properly before mashing them. 
  • Don’t add an already runny looking Shepherd’s Pie to the oven. Make sure you’re (almost) happy with the consistency before you add it to the oven. 

Then again, there’s always the option of just not bothering and looking for some great British places to eat out instead of making your own. 

But that’s not really the attitude now, is it?! 

Use Plain (All-Purpose) Flour

It’s firstly important to know that simply just adding plain, all-purpose flour to an already runny Shepherd’s Pie mixture, will probably just make things worse. You’ll likely just end up having clumps of flour in your dish that you won’t be able to get rid of (and a horrible, raw floury taste). 

That said, there’s plenty of Shepherd’s Pie recipes that include the use of flour.

If you choose to use flour, this needs to be done at an early stage of the cooking process, i.e. when you’re frying off the vegetables and lamb mince.

Just make sure you stir the flour (usually by the tablespoon) into the lamb / vegetables sufficiently, so it’s fully incorporated. Also, allow it to ‘cook out’ for a minute or two, which should avoid your finished Shepherd’s Pie tasting of flour.

As you might’ve already gathered, using flour is more of a preventative measure, rather than being a way of salvaging an already runny Shepherd’s Pie.

That’s where cornflour comes in…

Use Cornflour

Mix the cornflour with cold water (per the cornflour packet instructions) and stir into your runny Shepherd’s Pie filling (whilst over a low-medium heat). 

Once thickened to the desired consistency, turn off the heat.

Never add cornflour on its own. Make sure you mix the cornflour with (cold) water before adding to the Shepherd’s Pie.

Be aware that there’s an element of judgment and patience needed when using cornflour. Add the cornflour and water mixture gradually and allow a bit of time for the thickening to happen. Add more as needed. Don’t add too much at one time.

Alternative Ways To Thicken A Runny Shepherd’s Pie

Here’s a few other things you could use to thicken a runny Shepherd’s Pie:

  • Potato starch
  • Arrowroot 
  • Rice starch

There’s also other commercial thickening agents available, but we’d suggest just using one of the methods mentioned above. 

What Is The Best Way To Thicken Shepherd’s Pie?

Thicken runny Shepherd's Pie

While you don’t want your Shepherd’s Pie to be runny, it’s important to note that it shouldn’t be too thick or stodgy either.

What you want is a nice, luxurious looking consistency.

So, whatever you do, make sure you don’t use too much of your chosen thickening agent. 

Our suggestion would be to approach making your Shepherd’s Pie without even thinking it’ll turn out runny (glass half full and all that).

In other words, we’d avoid using plain flour at the outset. This could risk making the dish heavier than you want and it tasting of raw flour.

Instead, we’d say just be prepared to use cornflour and water, or one of the other alternative methods, if it turns out to be needed. They should work equally as well.

At the end of the day, anything’s better than a runny Shepherd’s Pie! 

Shepherd’s Pie Recipe

Check out our favourite video of Shepherd’s Pie being made (by none other than Gordon Ramsay), followed by a top-notch traditional Shepherd’s Pie recipe…

You’ll notice the recipe used by the G-Ram in this video includes some twists (like grating the carrots and onions rather than chopping them, and parmesan cheese rather than cheddar). You’ll have also noticed that he didn’t use any thickening agent (that we saw!) But don’t let that stop you if you need to.

Feel free to use both the video and the recipe below as a guide and make tweaks to suit your tastes and needs…


For the filling:

  • 25g vegetable oil
  • 1 large onion, finely chopped
  • 2 medium carrots, finely diced
  • 2 tbsp olive oil
  • 500g lamb mince
  • 2 tbsp tomato puree
  • 2 bay leaves
  • 2 sprigs fresh thyme
  • 400g tin chopped tomatoes
  • 2 tsp Worcestershire sauce
  • 450ml stock (chicken, beef, lamb or vegetable)
  • salt and black pepper

For the mashed potatoes topping:

  • 700g Maris Piper potatoes
  • 55ml milk
  • 75g butter
  • 1 egg yolk
  • Cheddar cheese (optional), quantity up to you!


  • Heat the vegetable oil in a large saucepan. Add the carrots and onion, cook for a few minutes.
  • Fry the mince (in the olive oil, in a large frying pan) until nicely browned. Break up and stir with a wooden spoon as you go.
  • Add the tomato puree to the onions and carrots. Stir. Then add the bay leaves, thyme and stir again. Add the chopped tomatoes, Worcestershire sauce and most of the stock (leave a little in the jug, to deglaze the mince pan).
  • Transfer the browned mince to the saucepan and pour your remaining stock into the empty mince pan, gently scraping any bits of mince at the bottom of the pan. Pour into the saucepan with the filling.
  • Bring to a boil. Add salt and pepper and allow to simmer for approximately 45 minutes, stirring regularly.
  • Preheat the oven to 200C / 180C Fan / Gas 6.
  • For the mashed potatoes topping, boil the Maris Piper potatoes until soft.
  • Drain the potatoes. Pass through a potato ricer or sieve (optional but recommended) before adding the butter, milk and egg yolk, then mixing together. Season with salt and pepper.
  • Grate and add your cheese at this stage if you want cheesy mash, or grate and put the cheese to one side, if you’d prefer cheese just on top of your mash.
  • Pour the meat filling into an ovenproof dish and spread the mashed potatoes on top. Decorate with a fork, or add your grated cheese.
  • Place the dish in the oven and cook until the toping is golden-brown.

There. We hope that helps you make an incredible (non-runny) Shepherd’s Pie!

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