• Grease 12 muffin cups or line with paper muffin liners.

• Cream butter and sugar with an electric hand-held mixer until light and fluffy. Beat in eggs, one at a time, beating after each addition. Add bananas and vanilla and beat until smooth.

• Mix together the flour, salt, baking powder, and baking soda. Stir flour mixture into butter mixture, alternating with the sour milk or buttermilk. Stir just until dry ingredients are moistened; gently stir in chopped nuts.

• Spoon banana muffin batter into prepared muffin cups or liners, filling about 2/3 full. Bake at 400° for about 15 to 18 minutes, or until tops are lightly browned. Cool banana muffins in pan on rack for a few minutes; turn banana muffins out onto rack to cool longer. Serve banana muffins warm.