Cream the butter and sugar together using an electric mixer until light and fluffy - about 3 minutes. With the mixer on low speed, add the eggs and vanilla and mix until well blended. Stir the cocoa powder, salt, and flour into the egg and butter mixture until everything is well combined.
Lightly coat an 8” pie plate with cooking spray. Pour mixture into the pie plate.
Bake for 30-35 minutes or until the center of the pie is set.
Remove from the oven and allow to cool for 10 minutes before serving.
Serve with vanilla ice cream and a drizzle of chocolate syrup.