GEOFF’s Crustacean Fennel and Leek Sauce…
⏱️ Enjoy with your favourite beverage | 4 min read
When I make crustacean stock from the shells and frames that would otherwise go in the bin, I freeze it in 20 ml cubes. They’re little flavour bombs that sit quietly in the freezer until I need them.
A few cubes can disappear into a pasta, risotto or soup, but sometimes I just want to grab a couple and turn them into something for dinner.
This is one of those.
I sauté fennel and leek in butter until soft and sweet, without colouring them, then warm them through with the stock and finish with cold butter and a few drops of aged sherry vinegar. The vegetables give the stock something to work with, and the stock brings another layer of flavour to the plate.
I keep it loose rather than reducing it, but there’s no reason not to reduce it further if that’s the sauce you want. I either leave the fennel and leek in as a trivet with a fish fillet on top, or strain them out and spoon the sauce onto the plate on its own. From start to finish, it takes about the same time as cooking the fish.
GEOFF’s Crustacean Fennel and Leek Sauce…
A couple of crustacean stock cubes from the freezer turned into a sauce for dinner. Fennel and leek are sweated in butter until soft and sweet, warmed through with the stock, then finished off the heat with cold butter and a few drops of aged sherry vinegar. It's kept loose rather than reduced, and takes about as long as cooking the fish: leave the vegetables in as a trivet under a fillet, or strain them out and spoon the liquid under seared scallops.
Ingredients
Equipment
Method
- 1. Melt 45gm butter in a wide frying pan on induction setting 4 (low-medium flame). Add the fennel and leek with 1.5gm salt. Cook gently for 5-7 minutes, stirring occasionally, until soft, translucent and starting to turn silky. If the edges begin to brown, turn the heat down – you want sweetness here, not colour.2. Add the 180ml crustacean stock. The cubes can go in straight from the freezer; they melt in a minute or two. Bring to a gentle simmer on induction setting 4 (low–medium flame) and warm through for 2-3minutes, until the stock has worked into the vegetables and there is still liquid around them.3. Take the pan off the heat. Add the 30gm cold butter a few pieces at a time, swirling the pan until each addition melts into the liquid and it turns glossy.4. Add 6ml aged sherry vinegar, stir and taste. Add up to3ml more if it needs it. The vinegar should sharpen the stock, not make the dish taste vinegary.5. Taste for salt. If your stock is well seasoned you may need very little more, up to another 1.5gm.6. Spoon the sauce onto warmed plates, with the liquid around the fennel and leek. Sit the cooked fish fillet directly on top and serve straight away.
Nutrition
Notes
Suggested Servings
- With the fennel and leek left in as a trivet under a pan-seared fish fillet, skin on or off.
- Strained, with the liquid alone spooned under seared scallops.
- Scatter the reserved fennel fronds over each plate just before serving.
- Sourdough on the side for the liquid left on the plate.
- Wine: a Clare Valley Riesling – its acidity sits comfortably alongside the sherry vinegar and the sweetness of the fennel.
Notes:
- The stock carries this dish, so the better the stock, the better the sauce. I make mine from whatever crustacean shells and frames I have – prawn, crab, bugs or crayfish all work.
- I freeze the stock in a silicone ice cube tray, then turn the cubes into a labelled container. At about 20ml each they measure themselves: allow 1½ cubes per person.
- The stock can also go in other directions: white wine and butter, saffron and cream, tomato, or finished with shellfish butter.
- Add the cold butter off the heat. On a hot pan it melts into a pool of fat instead of thickening the liquid.
- Make ahead: the fennel and leek can be sweated (step 1) a few hours before serving. Add the stock, butter and vinegar just before plating.
Fridge Friendly Instructions:
- Keeps for up to 2 days in a sealed glass container in the fridge.
- Stovetop: reheat in a small pan on induction setting 3 (low flame) with a splash of stock or water, stirring, for 3–4 minutes. Don’t let it boil or the butter will separate.
- Steam oven: 90°C for 5 minutes in a covered solid stainless container. Stir before serving.
- Microwave: 50% power in 30-second bursts, stirring between each, until just hot.
- Taste after reheating – a drop more sherry vinegar brings it back into line.
Freezer Friendly Instructions:
- The finished sauce is not suitable for freezing: the fennel goes limp and the butter separates on thawing. Freeze the stock, not the dish.
