Rum Raisin Oatmeal Coffee Cake

To make a long story short, I tried a new recipe for Oatmeal Raisin Bars and they turned out way way too sweet and gooey to use as a cookie.  To salvage them, I made them as the topping for a basic coffee cake that I dressed up a bit.  The franken recipe is a hit (at least with me).  

Gooey Rum Raisin Oatmeal Topping (can totally be made ahead) 

Raisins - get these started first. 

2/3 cup raisins
1/2 cup rum

1/2 cup water 

Splash of Vanilla

Plump the raisins. Put raisins, rum, water and vanilla in a small saucepan; if the liquid doesn’t cover the raisins, add more until it does. Put over medium heat. When it reaches a simmer, remove from heat and set aside to cool.

1 cup old-fashioned oats - Next get these toasted

Preheat the oven to 350F.   Scatter oats on a dry rimmed baking sheet. Toast 5-7 minutes, or until fragrant (Note they do not change much in color). Set aside to cool until you can handle them.

Final assembly: 

1/2 cup (1 stick) unsalted butter, cut into 8 pieces

3/4 cup + 2 T dark brown sugar, packed
1 large egg, room temperature
1 1/2 teaspoon pure vanilla extract
1/3 cup all-purpose flour
1 teaspoon ground cinnamon
pinch of Kosher or sea salt

Grease an 8- or 9-inch square pan. Line with parchment, leaving a little excess on two sides for ease of removal. Brown the butter. Place butter in a light-colored saucepan over medium heat. Let butter melt. Butter will bubble and crackle as the water content evaporates. Swirl the pan frequently for 5-7 minutes, keeping an eye on the color. When the solids are turning brown and the butter is nutty and fragrant, remove the pot from the heat and immediately pour the brown butter into a small-medium mixing bowl.

Add brown sugar to brown butter and whisk to combine. Mix in the egg and vanilla, followed by flour, cinnamon and salt. Mix in oats.  Pour raisins and water through a fine mesh sieve to discard water. Fold raisins into batter. 

Transfer batter to prepared pan and spread in an even layer all the way to the edges. Bake 25-30 minutes at 350, or until the top is set and a toothpick inserted in the center comes back with only a few moist crumbs (not batter).

Let this cool (overnight or more is fine)

Coffee Cake Base 

1 cup (143g) all-purpose flour

3/4 tsp baking powder

1/8 tsp baking soda

1/4 tsp salt

5 Tbsp (2.5 oz) unsalted butter, softened

1/2 cup (109g) granulated sugar

1 large egg

1 tsp vanilla extract

1/4 cup (2 oz) milk

1/4 cup (2 oz) sour cream or creme fraiche if you have it

Instructions

Preheat oven to 350 degrees. Butter an 8 by 8-inch baking dish then line with two sheets of parchment, butter parchment (alternately you can just butter and lightly flour the dish if you don't care to lift out the whole cake).

In a mixing bowl whisk together flour, baking powder, baking soda and salt for 20 seconds, set aside.

In the bowl of an electric stand mixer fitted with the paddle attachment, whip together butter and granulated sugar until pale and fluffy. Mix in egg and vanilla. In liquid measuring cup used to measure milk, whisk together sour cream with milk.

Add in 1/3 of the flour mixture to the butter mixture and blend just until combined, then add 1/2 of the milk mixture and mix just until combined. Repeat process once more, then end by mixing in last 1/3 of the flour mixture until nearly combined. Scape down sides and bottom of bowl using a rubber spatula and fold batter to fully incorporate.

Pour batter into prepared baking dish and spread into an even layer.  Now go back to your gooey topping and crumble it however you like (I used a knife then my hands) sprinkle liberally on the top (a good portion will drop through)  Leave some topping aside to put on the cake once it's out of the oven. 

Bake in preheated oven until toothpick inserted into center comes out free of batter and cake doesn't sink when touched in center, about 32 - 35 minutes. Cool in cake pan 10 minutes, then using parchment overhang lift cake from pan and cool on a wire rack. place the remaining topping on the coffee cake and cover with a kitchen towel.  

Enjoy!