Mr. D's Coffee Cake revisited

This post is not related to sourdough.  I described in a previous post, a coffee cake made by my college fraternity's cook, Mrs D.  The original recipe has a step involving a butter, sugar, and cinnamon, mixture with which I've never been quite clear about what to do.

Mrs. D’s Coffee Cake
Cream these items together
Sugar	1 Cup
Butter	2 Tbl
1 Egg
Add to that mixture
Milk	1 Cup
Flour	1 ½ Cup
Salt	½ tsp
Baking Powder	2 tsp
Pour into a well-greased 9x9 baking pan.
Cream the following ingredients together until all of the butter clumps are gone.
Sugar	½ Cup
Butter	1 Tbl
Cinnamon	1 Tbl

Those last three ingredients go on top of the coffee cake, but do I put them on before baking?  Do I melt them to make a glaze?  If so, do I put that on before or after baking?

I've tried it just about every way.  None of them have quite matched my memory of Mrs. D's coffee cake.  I have found that putting it on top of the batter, makes the cake gooey.  This time, I decided to save this sandy mixture until the cake was baked and just sprinkle it on top.

Astute readers have probably noticed that there aren't any baking instruction in the above recipe.  My original copy of the recipe said to bake for 30 minutes at 350 degrees.  The middle never seems to be cooked when tested with a toothpick.  The same was true for this batch.  I immediately put the cake back in the oven for another 10 minutes.

Sprinkling the second mixture on top after baking is the closest that I've come to my memory Mrs. D's coffee cake.  However, all of that crumbly goodness falls off when I eat a piece.

Next time, I'm going to try putting the whole shebang back in the oven for a minute or two after I sprinkle.  My next try at this recipe is going to be

Mrs. D’s Coffee Cake
Cream these items together
Sugar	1 Cup
Butter	2 Tbl
1 Egg
Add to that mixture
Milk	1 Cup
Flour	1 ½ Cup
Salt	½ tsp
Baking Powder	2 tsp
Pour into a well-greased 9x9 baking pan.  Bake for 40 minutes at 350°F
Cream the following ingredients together until all of the butter clumps are gone.
Sugar	½ Cup
Butter	1 Tbl
Cinnamon	1 Tbl
Sprinkle on top of the cake after baking and put it back into the oven for a few minutes.