How to Make It
Combine first 4 ingredients in a bowl with a pastry blender until mixture resembles small peas. Sprinkle with ice water, 1 tablespoon at a time; stir with a fork until ingredients are moistened. Shape dough into a ball, cover with plastic wrap, and chill 30 minutes.
Preheat oven to 425°. Roll dough into an 11-inch circle on a lightly floured surface. Fit into a 9-inch pie plate; fold edges under and crimp. Line pastry with aluminum foil, and fill with pie weights or dried beans. Bake 10 minutes. Remove pie weights and foil, and let cool completely.
Reduce oven temperature to 350°. Cook butter in a medium skillet over medium heat, stirring often, 5 to 6 minutes or until butter just begins to turn light brown. Transfer to a small bowl.
Whisk together eggs, lemon juice, and vanilla in a medium bowl until smooth. Add sugar and next 3 ingredients, whisking until smooth. Whisk in brown butter. Pour mixture into cooled piecrust.
Bake 30 to 35 minutes or until filling is lightly browned. Let cool completely on a wire rack.