Recipe creation, the Adjacent Possible & my first Fish Pie

On the weekend I decided to cook a fish pie. I enjoy fish pies when I eat them, which is relatively infrequent - to the point that I can probably count the number of fish pies I have eaten in my lief on my hands (or at least fingers and toes!).  As you might imagine, having eaten so few fish pies, I have never cooked one myself.

Now when I cook, by and large, I like to freestyle it (with the exception of cakes, where I follow recipes, but I don't frequently bake cakes).  Which can be a challenge when it comes to attempting to cook something I have never cooked before, so I thought as well as writing up my final recipe for the pie (which turned out pretty tasty, in my opinion) I would write a bit about my process.

I say process. I mean bumbling around trying to read enough to make sense of what is going on and not ruining dinner for us all.

The recipes I post here are all devised by myself, but they always borrow from lots of sources.  I think everyone does really, and very few recipes are genuinely original thought.  A while ago, after cooking my sausage and apple pie, my mum (my parents were visiting at the time)  asked if I had invented the recipe up myself, I answered yes, but at that moment, I felt a little bad taking credit for it, as really it was just the culmination of years of more informed, practiced people's success.  I certainly wasn't the first person to pair pork and apple, nor pairing pork and mustard, nor undoubtedly the first to put pork and apple into a pie!

There's an idea that is often used in reference to in innovation and invention that is the Adjacent Possible

The adjacent possible is a kind of shadow future, hovering on the edges of the present state of things, a map of all the ways in which the present can reinvent itself. (Steven Johnson - The Origin of Good Ideas)

What it really means, is at any given time, given everything we know, understand and have, there is the next step on from that, which is where innovation happens - this can be seen throughout history through lots of remarkable discoveries being made simultaneously by different people, in different parts of the world - that is, innovation isn't happening in the large, its the small increments from where we are (hence, the adjacent possible - the next thing), which is why at the same time, lots of independent people come up with the same ideas at the same time.

And that's the way I look at recipe creation - the adjacent possible. It is a different chronology for sure, as some of the ideas I am working on are decades old, but its the same principle. I take lots of other people's good ideas, and mix them together as I fancy.

There are some things that need to be exact, and there are some things that can be messed with - but once you start to understand what is happening when you cook, then identifying what these are then the more freedom you get to experiment with the components that you know won't make or break your end meal.

For example, on the very exacting, precise side you have things like pizza dough - here, the small details matter, and bakers work with very precise percentages mastering those. It's a known fact that salt slows down the fermentation process in dough (which I have only recently learnt, having just tried to make pizza dough!), so if you play too much with your salt percentages, then you need to understand that you need to also change your timings, and too much salt is just going to effectively kill the process for you.  On the other hand, basic things like aromatics (onions, leeks etc) are pretty much always inter-changeable, as they are bringing flavour - and thats something you can play with, to suit your own tastes (or food supplies).

Let's take an example of any slow cooked casserole I have featured on this blog. As I have mentioned in some of the posts, they are pretty formulaic, and it's really the discovery of this approach and flexibility that got me started on home recipe invention and learning what can be experimented with.

The basic components of my slow cooked casseroles are:
  • Fat - most commonly butter or oil etc
  • Aromatics - onion, leek, celery, carrot, etc, 
  • Flavour - I'm just using this term to categorise additional flavouring mustard,Worcester sauce, vinegar, tomato puree, soy sauce, fish sauce, herbs/spices etc - basically a fairly intense flavour "hit"
  • Liquids - stock/alcohol/water
  • Meat - lamb/beef/pork etc

As I'm sure you can guess, as these all have multiple options listed, these are all interchangeable, and by-and-large if you take a random combination of those listed above, you will likely get something at least halfway decent.

However, there is one important factor in your casserole that can't be messed with (too much) - that's the meat. Slow cooking is, like all cooking, a scientific process.  When you cook, the heat, over time, is altering the make up of the meat - in slow cooking specifically it is breaking down the collagen (in the connective tissue) which dissolves to gelatin, making for really succulent, tender and flavourful meat. Which is great news for pieces of meat like lamb shanks or beef short rib, which are cheap cuts of meat but high in connective tissue, but is exactly why you will never have any success slow cooking chicken breast, as it has very little connective tissue and will just dry out (but luckily, chicken breast is quick to cook anyway, so there isn't really any need to slow cook it!).

Having identified the constraints on the approach (the meat), we can be confident experimenting with the other factors to suit our taste, imagination or cupboards!

So, back to my fish pie.

The first thing I wanted to do was understand what makes up a fish pie and what constraints there are.  My normal approach to a new meal is just reading. I like to read recipes, even recipes for things that I know how to cook, as its always interesting to read ways other people have tried things, or find any interesting insights they have which can be borrowed in the future.

So I read several fish pie recipes, there seemed to be some variations: some people pre-poach the fish in milk before putting in the pie, some people don't use potato for the topping, and the fish itself varies too.

I wanted to make a classic style fish pie (creamy filling, mash potato topping) and from what I could tell (and based on what I know about the different components) the only constraint seemed to be that the fish was cooked (and not over cooked), which left me quite a bit of freedom to just pick the ingredients and flavours I wanted.


  • One fillet of cod (MSC approved, of course) without skin/bones
  • one fillet of smoked haddock without skin/bones
  • a handful of king prawns (I used pre-cooked prawns)
  • a handful of strong cheddar, grated
  • a teaspoon of chopped dill (fresh)
  • half a lemon
  • 200ml milk
  • tablespoon butter
  • tablespoon of flour
  • 2-3 bay leaves
  • 3 large potatoes (for mashing to top)


Preheat fan oven to 170 degrees centigrade
  1. Peel, chop and boil the potatoes to make the mash

  2. Heat the milk in a pan with the bay leaves

  3. Melt the butter in a pan, once melted add the flour and whisk into a smooth paste. Keeping over the heat, slowly add the milk, a little at a time - whisking each time until the mixture is smooth

  4. Chop the cod and haddock and toss into a casserole/pie dish a long with the prawns

  5. Throw in the chopped dill, a pinch of salt, the grated cheese and then squeeze the half lemon - stir the ingredients to mix through

  6. pour over the milk sauce (removing the bay leaves) and top with potato

  7. Put in the oven for about 40minutes, then serve

rob hinds Shambolically fumbling my way around the kitchen


  1. I always cook my fish first. I guess as it cooks quickly there's no real need. I also don't like prawns in pies as they can get chewy.

    1. I thought about poaching the fish in the milk that is then used for the white sauce, but was just too lazy. The prawns were a little tough to be honest, but still edible and I like the texture contrast they can provide against the softer ingredients.

    2. I thought about poaching the fish in the milk that is then used for the white sauce, but was just too lazy. The prawns were a little tough to be honest, but still edible and I like the texture contrast they can provide against the softer ingredients.