Preheat oven to 350 degrees, Line muffin cups with paper liners. Mix the flour, baking soda and salt together. Cream the butter and sugar in a mixing bowl until light and fluffy. Beat in the eggs and vanilla extract. Add the bananas and mix well. Stir in the dry ingredients until well incorporated. Stir in the chocolate chips. Spoon into the muffin cups. Bake for 20 minutes or until golden brown