Banana Muffin

My family loves bananas. I always keep bananas at home but most of the time I have to throw them away because they're not good anymore. This time I don't want to throw them away and I have to figure out what I'm gonna make. Well, I never make banana muffin before, seems to be my opportunity to try it.
Ingredients:
1/3 cup oil
3/4 cup brown sugar
2 eggs, beaten
1 tsp vanilla
1 tsp baking soda
pinch salt
1/2 cup milk
1 1/2 cups flour
4 ripe banana, mashed

Directions:
1. Preheat oven to 180°C.
2. Grease a 12 cup capacity muffin tin or use paper liners.
3. With a wooden spoon, mix all ingredients in large mixing bowl. Add mashed bananas at the end.
4. Pour mixture into a prepared muffin tin. Bake for 25 minutes. Cool on a rack.

*Cook's note: To check to see if the muffins are done; with a toothpick insert into the center of a muffin, if it comes out clean, it's done.