Line
twelve cups (each 2 1/2 inches wide) of a standard muffin tin with
paper liners; set aside. In a large bowl, stir together flour, sugar,
pumpkin-pie spice, baking powder, baking soda, and salt; set aside.
In another bowl, whisk together yogurt, butter, and eggs. Make a
well in the center of the flour mixture, and add yogurt mixture. Stir
until just combined. Fold in carrots.
Spoon batter into prepared muffin cups. (If desired, muffins can be
baked immediately in a 375 degrees F oven for about 20 minutes.) Freeze
until firm, about 30 minutes, then cover tin with plastic wrap, and
freeze until ready to bake, up to 3 months.
Preheat oven to 375 degrees F. Bake muffins (still
frozen) until a toothpick inserted in center of one comes out clean,
about 30 minutes. Transfer to a rack. Serve warm or at room temperature.