Leek Tart

Ingredients

• 1 ½ cups (7 ½ ounces) all-purpose flour
• 1/2 tsp. salt
• 4 Tbsp. vegetable shortening, chilled in the refrigerator 30 minutes
• 4 Tbsp. unsalted butter, cut into ¼ inch pieces, chilled in freezer 30 minutes
• 2-6 Tbsp. ice water
• 3 1/2 cups thinly sliced leeks (white and pale green parts only; about 2 medium)
• 3 Tbsp. extra-virgin olive oil
• 1 large red onion, thinly sliced
• 1 cup sliced green onions
• 1 large egg, beaten to blend
• 8 ounces Taleggio cheese, cut into small pieces
• 2 Tbsp. grated Parmesan cheese