Coffee Cake

Coffee cake is served with coffee, typically sweet and spiced to complement coffee’s strong flavor.  Coffee cake is another kind of cake with layers being baked together simultaneously.  Unlike the tarte Tatin, a layer of crumb, similar to Germany’s streusel, is spread and baked atop the cake batter.  Streusel means sprinkle or strew in German, referring to the crumbly topping of flour, oats, nuts, sugar, butter, and spices.  The cake itself, however, is usually made with oil for a tender and moist texture.  

The challenge to baking a layer atop the cake is how to keep it from burning while the cake batter still rises fully, being weighed down by the topping.  To get a proper rise, the cake is usually baked in a wide and shallow baking pan to shorten cooking time, which also prevents the top layer from being burnt from overcooking.  Unlike apples, the streusel does not sweat while being cooked, which could make for a sloppy cake from the extra liquid seeping down into it.

I once bought a fantastic coffee cake from a bakery.  It was a big round cake, piled high with cardamom flavored streusel.  I suspected that instead of baking the streusel with the cake, they cooked it separately and poured it atop the cake afterward.  But it inspired me to think about how I could make a round cake with streusel baked in.

Employing an acidic cake batter with baking soda for a fast rise is preferred when making this coffee cake.  Still, I found the streusel was too much burnt before the cake would be done.  After several tweaks to the oven settings, I found it best to bake it covered until the cake was cooked, then uncovered until the streusel was to desirable doneness.  It was also better to bake it at a lower temperature to prevent too much crust being formed along the cake wall.

This coffee cake is flavored with cardamom, orange zest, and coffee.  It is made with yogurt and baking soda to enable a fast rise.  The cake is rich and moist, while the streusel is buttery, crunchy, and nutty.

Instructions
Streusel: mash the butter into every other ingredient with a fork until a crumbly mixture is formed.  Alternatively, run a stand-mixer with paddle attachment until it is crumbly, but not mushy.  If you let it run for too long, the butter softens too much and binds the rest of the ingredients into a mush.

Sift together flour, baking powder, baking soda, salt, and the spices.

Whisk the egg with sugar until pale and frothy.  Add the vegetable oil, vanilla extract, and the orange zest and continue to whisk.  Fold the flour mixture and the yogurt into the egg mixture, ⅓ at a time, alternating between each.

Line a 6-in round baking pan with parchment paper well above the edge or use a tall 6-in round cheesecake pan.  Pour the cake batter into it and gently spread the streusel mixture atop.  1hr @ 325F, top covered with aluminum foil, then uncovered for 15-20 min @ 325F until the streusel is cooked to desirable doneness.