500g/1lb 2oz plain flour, plus extra for dusting
1 tsp caster sugar
2 tbsp caster sugar
1 tsp fine sea salt
1 x 7g/ΒΎoz sachet of fast-action dried yeast
175g/6oz butter, softened, plus extra for greasing
4 medium eggs, beaten
1 egg yolk, beaten, for glaze
125ml/4fl oz warm milk
1 large saucisson, or other soft French sausage