Leek Welsh Rarebit
Welsh rarebit sometimes gets treated dismissively as a shorthand for cheese on toast, which does it a genuine disservice. Done properly, the sauce is rich, glossy and deeply savoury, with the ale and mustard working in the background rather than announcing themselves. This version adds a layer of slow-cooked leeks underneath, which brings a quiet sweetness that balances the sharpness of the cheddar beautifully. It takes a little patience with the leeks, but nothing about this is difficult, and the result is far better than its reputation suggests.
Leek Welsh Rarebit
A deeply savoury Welsh rarebit made with slow-cooked leeks and a glossy brown ale and cheddar sauce, piped over sourdough and finished under a hot grill until golden and bubbling.
Ingredients
- 2 medium leeks, white and light green parts only, sliced into half rounds
- 55g unsalted butter (25g for the leeks, 30g for the roux)
- 30g plain flour
- 100ml brown ale or malty bitter
- 200g mature cheddar, grated
- 2 tsp English mustard
- 3 tsp Worcestershire sauce
- 1 egg yolk
- Flaky salt and black pepper
- 2 thick slices sourdough
Instructions
- Melt 25g of the butter in a wide pan over a low heat. Add the leeks with a pinch of salt and cook for 20 to 25 minutes, stirring occasionally, until completely soft, sweet and dry with no visible liquid remaining. Set aside.
- In a small saucepan, melt the remaining 30g butter over a medium heat. Add the flour and stir for a minute to cook it out.
- Add the ale a little at a time, stirring vigorously between each addition until smooth and thick.
- Stir in the mustard and Worcestershire sauce and season with black pepper.
- Remove from the heat and add the cheese in two or three batches, stirring well between each until fully melted and glossy. The mixture will be thick and may look slightly greasy at this stage.
- Beat in the egg yolk until fully incorporated and the sauce is smooth and cohesive. Transfer to a piping bag or bowl and allow to cool to room temperature.
- Lightly toast the sourdough on both sides until it has enough structure to hold the leeks and rarebit without buckling under the grill.
- Pile the leeks onto the toast and spread to the edges. Transfer to a baking tray.
- Pipe or spoon the rarebit mixture generously over the leeks, covering them completely right to the edges of the bread.
- Place under a high grill for 3 to 5 minutes until deeply golden, bubbling and beginning to char at the edges. Serve immediately with a simple salad.
Nutrition Facts
Calories
820Fat
52 gSugar
5 gProtein
36 gCarbs
48 gApproximate values per serving
Ingredient Notes
Leeks
Use only the white and light green parts. The darker green tops are tougher and more fibrous, and they won't cook down to the same silky texture. Go slowly, the leeks need a full 20 to 25 minutes over low heat to collapse properly and lose all their liquid. Rush this stage and you'll have a wet layer that steams the toast from underneath.
Mature cheddar
Grate it yourself from a block. Pre-grated cheese contains anti-caking agents that interfere with how the sauce melts, giving you a grainy or slightly gluey result rather than a smooth, glossy sauce.
Brown ale
A malty bitter or brown ale works best here. Something with body and a little sweetness, rather than a heavily hopped pale ale, which can turn sharp and bitter when reduced.
English mustard
Use prepared English mustard rather than powder for this recipe. It integrates more smoothly into the sauce and gives a clean, sharp heat without any graininess.
Zero Waste
Any leftover rarebit mixture keeps in the fridge for up to three days in a sealed container or piping bag. Bring it back to room temperature before using, then spread or pipe onto fresh toast and grill as normal. The leek tops that you trimmed off can go into a stock along with any other vegetable scraps.
Kitchen Notes
Getting the sauce right
The rarebit mixture should be thick enough to hold its shape when piped or spooned. It may look slightly greasy before you add the egg yolk, this is normal. The yolk brings it together and gives the finished sauce its cohesion and gloss. Beat it in off the heat and the sauce will smooth out.
Cooling matters
The rarebit needs to cool to room temperature before you use it. A warm or hot sauce will slide off the leeks and pool on the tray rather than sitting in place over the toast.
The toast
Toast the sourdough lightly on both sides before loading it. The bread needs enough structure to hold the weight of the leeks and rarebit through the heat of the grill without going soggy. A thick-cut slice is important here, thin sandwich bread won't manage it.
The grill
Get it as hot as it will go. You want rapid, direct heat that colours the top quickly without drying out the sauce underneath. Keep an eye on it from about 3 minutes in - you want deep golden colour and bubbling edges with just a little char, not a uniformly pale or overcooked result.
Variations
With a fried egg
A fried egg on top makes this a Buck Rarebit, the traditional British variation. Sit it on top just before serving and let the runny yolk run down through the cheese sauce as you eat.
With wild garlic
In season from March through May, a handful of wild garlic leaves chopped and wilted in with the leeks at the end of cooking adds a gentle, fresh allium flavour that works very well with the ale and cheddar.
With a different ale
A dark stout gives a slightly more bitter, roasted flavour in the sauce. Lighter options will give a cleaner, more neutral result. Experiment based on what you have, but avoid anything too heavily hopped.
Serving Suggestions
How to serve
Serve straight from the grill while the rarebit is still bubbling. A simple dressed salad alongside is all it needs. The contrast between the hot, rich toast and something cold and lightly acidic is perfect.
When to serve
One slice makes a satisfying lunch. If you're serving it as an evening meal, put out two slices each and add a proper salad alongside. It's also a very good thing to eat at any hour when the fridge is looking sparse but you have good bread, decent cheese and a half-drunk bottle of ale.
