father's day coffee cake

This was a great coffee cake!  The only thing I didn't like was how the recipe was written so I disregarded it and did my own thing.  I wasn't sure it would turn out as great as it did.

father's day coffee cake
2 cups flour
3/4 cup white sugar
2 teaspoons baking powder
1/2 teaspoon salt
1/2 cup butter, melted
1 egg
3/4 cup milk or as needed
1 1/2 teaspoons vanilla extract
1 teaspoon cinnamon

streusel topping:
1/4 cup flour
2/3 cup sugar
1 teaspoon cinnamon
1/4 cup butter

Preheat oven to 350 degrees.  Grease an 8x8 inch pan.  Make the strusel topping:  In a medium bowl, combine 1/4 cup flour, 2/3 cup sugar and 1 teaspoon cinnamon.  Cut in butter until mixture resembles coarse crumbs.  Set aside.
In a large bowl, combine 2 cups flour, 3/4 cup sugar, baking powder and salt.  Add melted butter.  Crack an egg into a measuring cup and then add milk to make 1 cup.  Stir in vanilla.  Pour into crumb mixture and mix just until moistened.  Spread into prepared pan.  Sprinkle with streusel.
Bake in the preheated oven for 25 to 30 minutes, or until a toothpick inserted into the center of the cake comes out clean.  Allow to cool.