Leek, Kale and Goat Cheese Strata

Ingredients

• 2 tablespoons butter, at room temperature
• 1 tablespoon extra-virgin olive oil
• 1 bunch leeks, thinly sliced
• 1 bunch kale, torn into bite-size pieces
• 1 loaf of bread, cut into 1-inch cubes
• 6 ounces goat cheese
• 8 eggs
• 1 cup milk
• ½ cup heavy cream
• 1 tablespoon Dijon mustard
• 1 teaspoon salt
• ¾ teaspoon freshly ground black pepper