*Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.
**Nutrient information is not available for all ingredients. Amount is based on available nutrient data.
(-)Information is not currently available for this nutrient. If you are following a medically restrictive diet, please consult your doctor or registered dietitian before preparing this recipe for personal consumption.
Place a steamer insert into a saucepan and fill with water to just below the bottom of the steamer. Bring water to a boil. Add butternut squash, cover, and steam until tender, about 25 minutes. Mash squash with a potato masher in a bowl and cool to room temperature.
Preheat oven to 350 degrees F (175 degrees C). Grease 15 muffin cups or line with paper muffin liners.
Beat butter and sugar together in a bowl with an electric mixer until fluffy, 3 to 5 minutes. Beat in eggs, 1 at a time, until mixture is foamy. Pour milk slowly into butter mixture while beating.
Fold mashed squash, baking soda, and nutmeg into butter mixture. Fold flour into squash mixture, folding from the bottom of the bowl to the top. Pour batter into prepared muffin cups.
Bake muffins in the preheated oven until a toothpick inserted in the center of a muffin comes out clean, 18 to 20 minutes.