The Best Coffee Cake Ever

This is seriously the best coffee cake.  The recipes says it is so, but I can attest to the fact that it is.  It was even better because my friend brought it over when she came to visit.  Eating coffee cake and visiting all morning was very Mad Men of us....

The Best Coffee Cake
 
FOR THE CAKE:
1-½ stick Butter, Softened
2 cups Scant Sugar
3 cups Flour, Sifted
4 teaspoons Baking Powder
1 teaspoon Salt
1-¼ cup Whole Milk
3 whole Egg Whites, Beaten Until Stiff
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FOR THE TOPPING:
1-½ stick Butter, Softened
¾ cups Flour
1-½ cup Brown Sugar
2 Tablespoons Cinnamon
1-½ cup Pecans, Chopped

Preheat oven to 350 degrees. Sift together flour, baking powder, and salt. Beat egg whites and set aside.
Cream butter and sugar. Add flour mixture and milk alternately until combined. Don’t overbeat. Fold in beaten egg whites with a rubber spatula. Spread in a well-greased 9 x 13 (or LARGER!) baking pan. A cake pan with higher sides would be best.
In a separate bowl, combine topping ingredients with a pastry cutter until crumbly. Sprinkle all over the top.
Bake for 40 to 45 minutes.