Rhubarb Pie Recipe: My Tangy-Sweet Rhubarb Reverie

Ingredients

• 2 ½ cups (315g) all-purpose flour, plus more for dusting
• 1 teaspoon (5g) salt
• 1 cup (227g) cold unsalted butter, cut into ½-inch cubes
• 6-8 tablespoons (90-120ml) ice water
• 1 tablespoon (15ml) apple cider vinegar
• 5 cups (approximately 600g) fresh rhubarb, trimmed and cut into ½-inch pieces
• 1 cup (200g) granulated sugar
• ¼ cup (30g) all-purpose flour
• 2 tablespoons (30ml) lemon juice
• 1 teaspoon (5ml) vanilla extract
• Pinch of ground cinnamon
• 2 tablespoons (30g) unsalted butter, cut into small pieces
• 1 large egg, beaten
• Coarse sugar, for sprinkling (optional)