Martha Stewart's Banana Bread

I got this recipe from My Sister's Cafe. I LOVE this banana bread recipe, it is very simple and classic, nothing funky, which I like! :)

1/2 cup butter
1 cup sugar
2 large eggs
1 1/2 cup flour
1 tsp baking soda
1 tsp salt
1 cup very ripe bananas, mashed (3 bananas)
1/2 cup sour cream
1 tsp vanilla extract
1/2 cup chopped pecans or walnuts (optional)

Preheat oven to 350 degrees. Butter 9x5x3 inch loaf pan; set aside. With an electric mixer, cream butter and sugar until light and fluffy. Add eggs and beat to incorporate. In medium bowl, whisk together flour, baking soda and salt. Add to butter mixture and mix until just combined. Add mashed bananas, sour cream and vanilla; mix to combine. Stir in nuts (if desired) and pour into pan. Bake until cake tester inserted into center of loaf comes out clean, abiout 1 hour. Let rest in pan for 10 minutes, then turn out onto a rck to cool.