Preparation time: 25 minutes, plus rising and cooling
Cooking time: 15-20 minutes
100g créme fraîche
1tbsp horseradish sauce
slightly salted butter, softened, for spreading
handful of watercress
24 thin slices of rare roast beef
salt and freshly ground black pepper
For the brioche buns
125ml warm water
1 x 7g sachet fast-action dried yeast
2tbsp warm milk
2tsp golden caster sugar
225g strong white bread flour, plus
extra for dusting
1tbsp unsalted butter, softened
1large egg, beaten
beaten egg, to glaze
sesame seeds, for sprinkling
For the brioche buns: Put the 125ml warm water, the yeast, warm milk and sugar into a bowl and leave to stand for 5 minutes until it starts to bubble.
Meanwhile, tip the flour and salt into a large bowl, add the butter and rub in using your fingertips until the mixture resembles fine breadcrumbs.
Make a well in the centre of the flour and add the yeast mixture and egg. Using your hands, mix together until it forms a sticky dough - don’t worry if the mixture feels a little wet at this stage, it will come together when kneading.
Knead the dough in the bowl for 10 minutes, stretching it up and out of the bowl with your hands - it will still be very sticky. The dough is ready when it feels soft and bouncy and will stretch up high without breaking. Cover the bowl with clingfilm and leave to rise in a warm place for about 30 minutes, or until doubled in size. Line two baking sheets with baking paper. Knock back the dough by punching out the air, then turn out on to a lightly floured surface and knead for 2 minutes.
Divide into 12 equal pieces, then roll into balls and place on the prepared baking sheets.Loosely cover with a damp, clean tea towel and leave to rise for 30 minutes until doubled in size. Preheat the oven to 200°C.
Brush the buns with the beaten egg and sprinkle with sesame seeds.
Bake in the oven for 15-20 minutes, or until golden. Transfer to a cooling rack and leave to cool. In a small bowl, mix the créme fraîche and horseradish together, then season to taste.
Cut the brioche buns in half horizontally, then butter the cut sides. Spread over the horseradish cream, then add some watercress and two folded beef slices to each.
Top with the brioche lids and serve.