Brioche with Périgord truffle

Ingredients

• 20 g yeast
• 7 g sugar
• 7 g salt
• 85 g butter
• 116 ml milk
• 1 piece(s) egg
• 30 g egg yolk
• 360 g white flour
• 2 tbsp Mascarpone
• 1 tsp. truffle oil
• 100 g butter
• 50 g Périgord truffle / summer truffle
• salt, pepper, nutmeg, sugar