Preheat the oven to 350°F (175°C). Line a muffin tin with 8 muffin liners.
In a medium bowl, cream together the butter and brown sugar.
Next, mix in the flour, ginger, cinnamon, and nutmeg.
Add in the eggs, and mix until smooth.
Fold in the grated carrots until evenly distributed throughout the batter.
Divide the batter evenly among the 8 muffin liners, filling each about two-thirds full.
Bake in the preheated oven for 18-22 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
Allow the muffins to cool in the tin for 5 minutes, then transfer to a wire rack to cool completely.