Glamorgan toastie

Ingredients

• 60 gunsalted butter
• 2 tspolive oil
• 1 smallleek or small onion, finely sliced
• 80 g (about 4)leftover cooked Brussels sprouts, finely sliced
• 4 slicesthick white bread (bloomer or farmhouse)
• 4 tspEnglish mustard
• 80 ggrated extra mature cheddar cheese
• 40 gStilton, crumbled

Instructions

1. 1

   Cook the filling

   Melt 10 g of the butter with the olive oil in a frying pan. Sauté the leek or onion for 5 minutes, until it begins to soften. Add the sprouts and cook for a further 3–4 minutes, until lightly golden and heated through. Season, transfer to a bowl and set aside.

2. 2

   Build the sandwiches

   Butter one side of each bread slice and spread mustard on the other. Put half the cheese on the mustard side of two slices, add the cooked leek mixture, then top with the remaining cheese. Place the other slices on top, mustard-side down.

3. 3

   Fry until golden

   Warm the frying pan over a medium-low heat. Fry one sandwich at a time, gently pressing it with a spatula, for about 3 minutes until the underside is golden. Flip and cook the other side until golden and the cheese has melted and started to ooze. Transfer to a plate and repeat with the second sandwich. Slice and serve immediately. Check that your cheese is vegetarian, if required.

What is a Glamorgan toastie?

Glamorgan toasties take their cue from Welsh Glamorgan sausages, a meat-free combination traditionally built around cheese and leek. This version turns those flavours into a hot sandwich, with Brussels sprouts and two kinds of cheese tucked between slices of bread.

The mix works because cheddar melts into a savoury base while Stilton brings a sharper, creamy note. Leftover cooked sprouts add texture and make the filling a useful home for cheeseboard odds and ends.

Nutrition and macros by portion

The nutrition label shows one serving as written: 746 calories, 25g protein, 41g carbs, 52g fat.

The bread supplies most of the carbohydrates, while butter and cheese account for much of the fat. Cheese also contributes protein, with the leek and sprouts adding vegetable flavour and texture. Serve with a generous salad or other non-starchy vegetables to balance the plate.

Choose the cheese

Cheddar: Extra mature cheddar gives the filling a strong savoury flavour and melts readily when grated.

Stilton: Crumbling it helps distribute its distinctive flavour through the sandwich. If using another cheeseboard combination, pair a firm cheese with one that melts well.

Cook the vegetables first

Leek or onion: Give it the full 5 minutes to begin softening before adding the sprouts. This helps the filling become tender rather than leaving sharp, raw-tasting pieces.

Sprouts: Slicing the cooked sprouts lets them heat through and catch a little colour in the pan. Let the mixture cool only briefly before assembling, so it is easier to handle.

Layer for an even melt

Cheese on both sides of the vegetable layer helps hold the filling together as it melts. Spread the filling across the bread rather than piling it into the centre, which makes each bite more balanced.

Keep the butter on the outside and the mustard on the inside. The mustard seasons the filling, while the butter helps the bread brown in the pan.

Watch the heat

A medium-low pan gives the bread time to turn golden while the cheese melts. If the heat is too high, the outside can darken before the middle is hot.

The underside is ready to flip after about 3 minutes, when it is golden. Cook the second side until the cheese is melted and beginning to ooze.

Serve straight away

These toasties are best sliced and eaten as soon as they come out of the pan, while the bread is crisp and the cheese is molten. A simple green salad or crunchy slaw makes a fresh contrast to the rich filling.

If serving with soup, choose a light vegetable soup so the meal stays centred on the toastie rather than adding another heavy element.

Recipe notes & tips

• Grate the cheddar finely so it melts evenly through the filling.
• Spread the mustard close to the edges of the bread for flavour in every bite.
• Use cooked sprouts that are well drained so they do not make the filling watery.
• Press gently with the spatula; pressing too hard can squeeze the filling out.
• Cook the sandwiches one at a time if your pan cannot hold both without crowding.

Variations

• Swap the blue cheese: Use another strong, crumbly cheese alongside the cheddar.
• Try red Leicester: Pair it with Stilton for a colourful, melting filling.
• Use taleggio: Combine it with a firmer cheese for a soft, rich centre.
• Change the alliums: Use finely sliced onion instead of leek, as in the ingredient list.
• Add extra mustard: Increase the mustard slightly if you like a more pronounced tang.

Common mistakes to avoid

• Starting with a hot pan: The bread may brown before the cheese melts; use medium-low heat.
• Using whole sprouts: Slice them finely so they heat through and fit neatly in the sandwich.
• Overfilling the bread: A thick mound can spill out; spread the mixture in an even layer.
• Skipping the butter: Butter the outside of each slice to help it turn golden in the pan.
• Flipping too soon: Wait until the underside is golden so the sandwich holds together.

How to store

For the best texture, eat the toasties straight away. If you have leftovers, refrigerate them in a covered container and reheat in a frying pan over low heat until hot throughout; the bread may be softer than when freshly made.

Frequently asked questions