Preheat oven to 350. Grease a 8x8 pan.
Cream together butter and sugar. Incorporate eggs and vanilla until combined. Mix in Nutella until smooth and fluffy. Add in flour and salt until just mixed.
Scoop batter into prepared pan and spread evenly. Bake 30 minutes or until set in the center.
Cool at least 10 minutes. Cut into squares and serve.