This is the BLUE BERRY MUFFIN recipe I constantly use.

http://allrecipes.com/Recipe/To-Die-For-Blueberry-Muffins/Detail.aspx

And here's the topping that I use-(off of the review) Supposedly lighter!

Mix them together with fork

2/3c. brown sugar
1/4 flour
1/4 tsp cinnamon
2T butter (room temperature works better)

This makes a lot so keep them in the fridge until next time!

I actually haven't made muffin with this, but I use mini loaf pan (has 8 1/2 x 3 1/2) and makes 7.
Baking time for that is 17-18 min.

Make sure to grease the cups. Otherwise, you will have messy one!

Even though one of the reviews say not to use frozen blueberries, I do and turn out fine. I just bake them a little longer. I have made it with dried blueberries and that's good too. However, if you prefer juicy and moist muffin with blueberries exploded(get the sponge around them moist), do not use the dry one. Someone said this recipe can be doubled and works well with other fruits so I am going to try it with strawberries next time.

Here's strawberry one

I made it with strawberries I had frozen. I used about 7 of them, just chopped them up and mixed them in. I actually liked this one more than blueberry ones. It tastes a little sweeter but so yummy! Maybe I will go for banana next :)