Preheat oven to 350F degrees.
Spray a 9-inch pie plate with nonstick cooking spray.
In a small saucepan, over low heat, cook butter and chocolate.
Stirring often until melted (then take off heat).
Beat eggs at medium speed with an electric or stand mixer for 5 minutes.
Gradually add sugar, beating until blended.
Then gradually add chocolate mixture.
Then add flour and vanilla extract, beating until blended.
If you’re using a stand mixer, it’s important that you continually scrape down the sides so everything mixes evenly.
Stir in 1/2 cup chopped pecans.
Pour into pie plate.
Bake at 350F for 35-40 minutes.
The center should be firm when finished.
Let pie cool.
Then slice and serve with ice cream, chocolate syrup and remaining chopped pecans.