Cheesy Mushroom Kale Challah Bread Pudding

Ingredients (14)

• 1/4 cup unsalted butter
• 1/4 cup extra virgin olive oil
• 1 large yellow onion
• 6 cup cremini mushrooms
• 1 Tbsp. fresh thyme leaves
• 2 Tbsp. dry white wine
• 2 large eggs plus 1 large egg yolk
• 1 cup whole or 2% milk
• 1/2 tsp freshly grated nutmeg
• 1/2 tsp ground cayenne
• 8 oz challah bread
• 2 cup shredded Gruyère or cheddar cheese
• 4 cup Tuscan kale leaves
• Salt and freshly ground black pepper