The Mushroom and Thyme Tart - Petites Choses

Ingredients

• 200grs plain flour, sifted
• 100grs finely ground walnuts or almonds
• 20grs of finely grated parmesan cheese
• 100grs cold unsalted butter, cubed
• 1 medium egg, lightly beaten
• A pinch fine sea salt
• 1-2 tbsp milk, to bind
• 25grs unsalted butter
• 2 shallots or small red onions, finely chopped
• 2 tsp thyme leaves
• 450grs mixed mushrooms , (whatever you can find, a mix of wild, big and small, roughly sliced)
• 200ml creme fraiche , (full fat sour cream)
• 150ml cooking cream , (double or full fat)
• 2 large eggs
• 1/2 tsp of fine sea salt
• 1/2 tsp of freshly cracked black pepper