Stroopwafel (Syrup Waffle)

Name: Stroopwafel (Syrup Waffle)
Prep time: 45 min
Cook time: 20 min
Total time: 1 h 5 min
Yield: 12 servings
Cuisine: Dutch
Ingredients: 300 g plain flour; 125 g butter; 75 g soft brown sugar; 1 egg; 5 g instant dried yeast; 100 ml milk; 0.5 tsp ground cinnamon; 0.5 tsp salt; 200 g dark brown sugar; 150 g golden syrup; 60 g butter; 1 tsp ground cinnamon; 1 pinch salt; 1 thin waffle iron; 1 serrated knife; 1 round cutter

The Dutch wafer baked thin in a grid-patterned iron, split horizontally through its own thickness while it is still hot, spread with syrup on the cut face and pressed back together. The syrup is not a filling; it is a softener. Krumkake says of the same kind of thin wafer that filled ones go soft within half an hour, which is why they are kept empty in a tin — and a stroopwafel is built to do exactly that. The syrup holds on to water, and over a few hours it pulls two crisp wafers chewy from the inside. So this is a biscuit that is better for having waited, and the only hard part is the split: a wafer off the iron stays cuttable for seconds.

Steps

Stir the yeast and a pinch of the brown sugar into the lukewarm milk and leave it 5 minutes. Mix the flour, the rest of the sugar, the cinnamon and the salt, then work in the melted butter, the egg and the yeasted milk to a soft dough. Knead it only 2-3 minutes — nothing here rises, so there is no reason to build gluten.
⏲ 10 min
Cover it and leave it somewhere warm for 45 minutes. It will not obviously grow; you only want it slackened.
⏲ 45 min
Make the syrup meanwhile. Put the dark brown sugar, golden syrup and butter in a small pan, stir over low heat until melted, and take it to 110-115°C and no further. On the ladder in what sugar does that is the syrup stage, before any colour; past it, the syrup sets like glass on cooling and cannot be spread. Stir in the cinnamon and salt, take it off the heat and keep it warm.
⏲ 15 min
Divide the dough into 12 pieces of about 45g and roll them into balls. Heat the iron.
⏲ 10 min
Put one ball in the middle of the iron, close it and bake about 40 seconds — pale gold is enough. Baked dark, it sets hard before you can split it.
⏲ 40 sec
The moment it comes off, trim the ragged rim with the cutter and lay the serrated knife flat into the edge to split the wafer through its own thickness. Push the blade through; do not saw. This is the whole biscuit and you have about 15 seconds — cold, it does not split, it shatters. Your fingers will complain, so a cloth glove helps.
⏲ 15 sec
Spread a tablespoon of the warm syrup over the cut face, put the two halves back together and press gently with your palm. Both have to be warm for the syrup to soak into the cut surface; hot syrup onto a cooled wafer just sets on top and glues the halves together.
⏲ 30 sec
Rack them and leave them at least two hours. That wait is part of the cooking: the syrup holds on to water and the crisp wafers turn chewy from the inside. Overnight is better still.
⏲ 120 min

Tips & Variations

Variations

It is the exact inverse of krumkake. That page records that a filled thin wafer "softens within half an hour, so unfilled is really the default." Same thinness, same patterned iron, same glass transition — and here that softening is the point. The reason not to fill one and the reason to fill this one are the same fact.
A different family from the Brussels waffle and the Liège waffle. Those are thick, deep-pocketed, and eaten as breakfast or as a street snack; this is a thin biscuit for coffee. The iron is different too — a shallow grid and a wider round. Easiest to think of it as an Italian pizzelle split in half.
Size: 10cm across is the old standard, but they are made anywhere from 5cm to 25cm now. If it is going to sit on top of a cup, it has to be wider than the cup.
Gouda, around 1810: it began as a cheap biscuit a baker made from leftover dough, crumbs and leftover syrup. It spread to the markets during the 19th century and is a supermarket and souvenir-shop item today.
The photograph is home-made, and its uploader wrote that his "stroop filling tastes too much like Dutch pancake syrup." That is exactly where a home version usually goes wrong. Dutch stroop is dark and thick, closer to molasses, and a clear syrup alone will not taste of it — which is why the sugar here is the darkest brown you can get and the syrup is golden rather than clear.
A caramel made not to set. Bündner Nusstorte adds cream to a caramel so it will not set; lokum uses acid to make invert sugar so it never crystallises. Here the temperature is stopped at the syrup stage and the golden syrup keeps the crystals away. All three are after the same thing — sugar that stays soft.
As an ice cream sandwich: ice cream between the halves instead of syrup, which removes the one thing the syrup was doing, so it has to be eaten at once. Common outside the Netherlands.
Gluten-free and mini: even market stalls make gluten-free ones now, and the 5cm size is what comes taped to a bag of coffee.

Tips

Split it hot. The hard part of this biscuit is neither the dough nor the syrup; it is those fifteen seconds. The description on the photograph says it in the baker's own words: you have to do it straight off the grill because they harden fast.
One at a time. Bake two together and the second sets before you get to it. Not doing anything else while the iron is closed is the technique — the same order of work as krumkake.
Push the serrated knife, do not saw it. Sawing crumbles the wafer. Lay the blade flat into the edge and push it through in one movement.
Hold the syrup temperature. 110-115°C. If colour has started you are already late, and the pan carries it another 20-30°C after the heat is off.
Bring the syrup back if it stiffens. Warm the pan again or stand it in hot water. Do not thin it with water.
Rest it over a cup of coffee and the steam loosens the syrup until it runs. That is how they are eaten in the Netherlands. Serving temperature has a section on dishes that are waiting on purpose; for this one the waiting is the cooking.
Keep them in an airtight tin. If they go softer over a few days, that is the syrup doing its job.