Adjust oven rack to lower middle position and heat oven to 375 degrees. Mix flour through nutmeg in medium bowl; set aside.

Beat butter in large bowl of electric mixer or with handheld mixer at medium speed until light and fluffy, 1 to 2 minutes. Add brown sugar, increase speed to medium-high, and beat until combined and fluffy, about 1 minute longer. Add eggs one at a time, beating thoroughly before adding the next. Beat in vanilla, molasses, and sour cream until thoroughly combined and creamy, about 1 minute longer. Reduce speed to low; beat in buttermilk and half the flour mixture until combined, about 1 minute. Beat in remaining flour mixture until incorporated and slightly curdled looking, about 1 minute longer, scraping sides of bowl as necessary. Stir in bran and raisins.

Spray a twelve mold muffin tin (each mold measuring 1/2 cup) or a six mold muffin tin (each mold measuring one cup) with cooking spray or coat lightly with butter; divide batter evenly among molds using spoon or ice cream scoop. Bake until a toothpick inserted into center withdraws cleanly or with a few moist particles adhering to it, about 25 minutes. Set on wire rack to cool slightly, about 5 minutes. Remove muffins from tin and serve warm.

Cook's Notes: Wheat bran is available at health foods stores or in boxes, labeled Quaker Unprocessed Bran, in supermarkets.

Formatted to MasterCook on 2/7/98 by Tsl. Tested, too!!!