These muffins and the buttermilk spice muffins are the two top-sellers among the several muffins baked every day at the Irvine, California-based chain. If you like the combo of carrots, raisins, and walnuts in a super-moist cake, this is the muffin for you. The real thing is made dark with the addition of caramel coloring which you can find in many supermarkets or in stores which sell cake-decorating supplies. You can choose to skip this ingredient and your muffins will still come out great. They’ll just be a little lighter in color. This recipe is designed for a large muffin pan with 6 large muffin cups, but you can also use a standard-size 12 cup pan. Just reduce the baking time by 5 to 10 minutes.