Thursday, June 20, 2013

Rhubarb Crumb Cake (Apple variation at the end of the recipe)

This is an awesome crumb cake, adapted from a recipe by Melissa Clark. The original was printed in the New York Times in June, 2007.

Rhubarb is a perennial vegetable, used more like a fruit. Everything I've read says that it's easy to grow, but after much angst and many dead crowns I've decided that I shouldn't plan to start a local fruit stand selling rhubarb - it won't grow in our yard (our "farm"). The culprit are the gorgeous 75 foot black walnut trees, which have made it necessary for us to become resourceful about what and how we plant.  As the kids in the family know, mostly from my groaning, the walnuts make it difficult, if not impossible, to grow any nightshades (tomatoes, peppers, and  potatoes).  The trees are also toxic to asparagus (we're working on a work-around for this), blueberries, rhododendron (and thus azalea), and peony. Rhubarb was not mentioned in most of the sources I consulted when I first started gardening in this particular yard, so it only dawned on me that it might be a problem after trying to start rhubarb crowns for three years running (no snide comments....please). Anyway, we are able to buy rhubarb locally including at the summer farmer's market in town. The rhubarb used in the cake pictured here was picked up at the DuPont Circle Farmer's Market in Washington DC.

I promise: this is an easy cake to make .  It's not particularly sweet and has a great ratio of crumb topping to cake (meaning:lots of topping).  The instructions are detailed and thus make it look complicated. This cake is easy to put together, tastes great, freezes fabulously.  The original recipe made one cake; I'm a lazy baker, I'd rather make 2 cakes and freeze one for another occasion.


Choreography:
There are 3 components to this cake: the rhubarb filling, crumb topping and batter. There is just enough batter to hold the rhubarb together and support the crumb.

To complete the cake in one baking session, make (and then chill) the crumb topping, prepare the rhubarb filling, mix the cake and assemble in the pans. The crumb topping will be like a very thick dough, chilling it will help you break it into large  pebble-like pieces (1/2 inch or so).



 I've used disposable tube pans for these cakes. Disposable pans make it easy to freeze the finished product and best of all - no more forgotten pans left at your friend's homes! I usually get my disposable pans on-line at Plastic Container City, although there are many other sources to go to. Spray with Pam or another vegetable spray before you assemble the batter in it. Note: disposable pans must be supported by a baking sheet and they do get greasy on the bottom while baking.

Equipment:
tube shaped baking pans
baking sheet or cookie sheet
mixer (stand or portable)
measuring spoons, cups
silicone spatula
mixing spoon

Ingredients:
This list will yield 2 cakes, if you want to bake only one, divide the recipe in half.

For the crumb topping:
2/3 c brown sugar (dark or light)      
2/3 c granulated sugar
2 tsp cinnamon
2 tsp vanilla sugar
1 tsp ground ginger
large pinch salt
1 cup melted margarine (or butter if you are making a dairy cake)
3.5 cup flour (fluff up the flour and measure lightly - or use 15.5 oz flour)

For the rhubarb filling:           
1 lb rhubarb. Trim the leaves and bottom of the stem, these parts are poisonous!! Slice the stalk into 1/2 inch slices
1/2 cup granulated sugar
2 Tbsp cornstarch

For the cake:
2/3 cup plain non-dairy yogurt substitute (I like to use coconut based yogurt, but soy or almond are fine) **
2 large eggs
2 yolks                                            
2 tsp vanilla extract
1 tsp lemon juice **
2 cups all purpose flour
1 c granulated sugar
1 tsp baking soda
1 tsp baking powder
1/2 tsp kosher salt
12 Tbsp margarine (a full quarter lb bar and 3/4 of a 2nd one) . Use butter if you are making a dairy cake

** if you are making a dairy cake use sour cream instead of non-dairy yogurt and omit the lemon juice

Procedure:
1.For the crumb topping:
Combine the dry ingredients in a medium sized bowl. Pour the melted margarine into the bowl and mix. The mixture will be very thick. Chill the mixture while you prepare the rhubarb and cake batter.

2. For the rhubarb filling:
Combine the rhubarb, sugar and corn starch. Mix with a spoon and set aside.

3. To make the cake: Preheat the oven to 350 degrees.
In a small bowl or measuring cup, combine the non-dairy yogurt, lemon juice, vanilla and eggs.

Combine liquid ingredients




and mix 


4. Combine the dry ingredients (flour, baking soda, baking powder and salt). Take the extra minute it will add to the process and sift the ingredients together. This will avoid any baking powder lumps or salt grains sticking together. It helps distribute the leavening agents.  You don't need a fancy sifter, a fine mesh strainer will do. The one pictured here has been in use for over 30 years, it's an incredibly useful tool when I bake.
Sifting the dry ingredients takes a minute and ensures better results



5. Cream together the margarine and sugar. 








6. Add about half of the "yogurt" mixture, alternating with half of the dry ingredients, then the remaining yogurt mixture and finish up with the dry ingredients. Work the batter at low speed and mix until just moistened. Don't over mix, unlike bread baking, you are not looking to build up gluten.





7. Measure out 1 cup of batter and set aside. This cake does not contain a lot of batter -don't worry, you'll have just enough.  I described this cake to a colleague as the closest thing to a pie, but making cake batter instead of a pie crust.





8. At this point you have all of the components prepared and you'll assemble the cake by spreading a thin layer of batter in the bottom of two prepared pans. Use all of the batter in the mixing bowl.

9. Sprinkle half of the rhubarb mixture on top of the batter in each pan. 





10. Using the reserved batter, drop "dollops" of batter on top of the fruit filling in each pan. You won't have enough batter to completely cover the filling.





11. Remove the crumb topping from the fridge and break up the clump into small chunks, about 1/2 inch in diameter. Drop half of the crumb topping on each of the two cakes. Try to distribute the pebble size crumbs evenly.


 12. Place both cakes on a baking sheet for support and bake in the preheated oven for 45-55 minutes. Test with a toothpick to determine whether it's cooked through or not. The rhubarb may make it a bit moist.

13. Cool before serving or freezing.  This cake may be double wrapped in plastic wrap and frozen for several weeks.

I have made a variation of this cake using an apple filling.  
For the apple version make the topping as above. For the filling: combine 5-6 apples, peeled and coarsely chopped, combined with 2/3 c brown sugar, 1 tsp ginger, 1 tsp cinnamon and 2 Tbsp cornstarch.  For the cake batter: 1 2/3 non-dairy sour cream or yogurt substitute, 1 tsp white vinegar, 2 large eggs, 2 yolks, 4 tsp vanilla extract, 4 cups flour, 2 cups granulated sugar, 2 tsp baking powder, 2 tsp baking soda, 1/2 tsp kosher salt, 1 3/4 sticks margarine. Follow the same process as above. Bake for 60-70 minutes.