Preheat the oven to 375 degrees F (190 degrees C). Grease and flour a 9-inch round cake pan.
Combine carrots, sugar, oil and eggs in a blender; blend until smooth. Gradually add flour and mix until well blended. Turn off blender. Stir baking powder into batter with a wooden spoon. Pour batter into the prepared cake pan.
Bake in the preheated oven until a toothpick inserted into the center comes out clean, 30 to 40 minutes. Place cake pan on a wire rack and cool completely. Run a table knife around the edges to loosen. Invert carefully onto a serving plate.
