Prick the pie crust with a fork. Bake it for 8 minutes at 350°.
Meanwhile, whisk the eggs. Then add the brown sugar and whisk vigorously.
Add the flour, syrup, butter, and vanilla. Whisk.
Remove the crust from the oven and fill with the egg mixture.
Bake for 35 to 40 minutes or until the top is brown and center is set. It can be 'slightly' jiggly in about a 2-inch circle in the very center. Thank will firm up as it cools.
Cool pie completely before cutting and serving.
Store in an airtight container on the counter for 4 to 5 days or in the refrigerator for 6 to 7 days.