Combine flour, baking powder, baking soda, salt and cinnamon; set aside.
In small bowl, beat butter until creamy. Gradually add sugar, beat 1 minute or until light and airy. Add brown sugar. Beat in eggs, one at a time. Beat in sour cream and vanilla.
Stir into flour mixture only until dry ingredients are moistened.
Fold in strawberries and nuts.
Pour into a greased 8 x 4 inch loaf pan.
Bake at 350°F for 60 to 65 minutes or until toothpick comes out clean.
Let stand 10 minutes in pan.
Turn out on rack to cool.