BBC Food - Recipes - Gâteau à la crème

Ingredients

• 250g/9 oz strong plain flour, preferably organic
• 3 pinches sea salt
• 2 tbsp caster sugar
• 1 x 7g packet dried yeast
• 3 free-range eggs , preferable organic
• 175g/6 oz unsalted butter , cut into small cubes
• 3 free-range egg yolks , preferably organic
• 3 tbsp caster sugar
• 1 lemon , juice and zest
• 125ml/4fl oz crème fraîche
• 1 free-range egg yolks , preferably organic
• 2 tsp caster sugar
• 10g butter , cut into cubes (optional)
• 1 tbsp nibbed sugar , to decorate