Pineapple cake

This is a very beautiful and yummy cake. My husband's colleague got this cake to office for a potluck. He came home and described the cake so nicely that....that I got the recipe and tried it..I got this recipe from food network website, but i split the ingredients to half(that's why the measurements of ingredients sound weird), since the reviews said that it was too much batter for one cake.

INGREDIENTS:
1.5 cups All purpose flour
1.125 cups Sugar
1.5 cups butter, 1/4 cup melted butter.
2 eggs
1/2 teaspoon vanilla extract
1 teaspoon baking powder
0.125 teaspoon salt
0.625 cups buttermilk
0.75 cups brown sugar
1 can pineapple with juice (well drained)
Reserve 2 table spoons juice for frosting.
Chopped pecans for garnish.

Pineapple butter cream frosting:
1/2 cup butter softened.
2 table spoon pineapple juice reserved.
3.5 cups confectionery sugar.
Beat above ingredients in a large bowl till well combined.

METHOD:
Preheat oven at 350F.
Spray the pan with cooking spray and sprinkle some flour.
In a large bowl, beat 1/2 cup butter until creamy. Gradually add sugar, beating until fluffy. Add eggs at a time. Now add vanilla essence.
In a small bowl take flour+ baking powder+ salt
Add flour mix into egg mix, alternating with buttermilk, beginning and end with flour.
Now comes the fun part:) Spread brown sugar in the cake pan. Pour melted butter (1/4 cup) over the brown sugar evenly. Arrange pineapple slices over the brown sugar.
Pour batter on top of it and bake for 40-45 min.
After baking cool the cake for 10 min, and invert the cake onto a base.
Frost the side with Pineapple butter cream frosting and press chopped pecans on sides.