Rhubarb Upside Down Cake

I'm thrilled to announce hothouse rhubarb appeared in Fresh Market last week! You know me and rhubarb.  So I came home with a couple pounds and proceeded to make the first entry in my annual spring rhubarb love-in. More recipes on the way, of course.
As a start, I found a fantastic upside down cake recipe using rhubarb. The cake nearly floats away it's so light and it has a slight lemon flavor. Ever so slight. It takes a few steps, but it's simple enough to make and it's a cake to make you proud to serve to friends and family for dessert. It's elegant, bright, makes a beautiful presentation and the flavor is ambrosial. What more could you ask? Love, love love.

Rhubarb Upside Down Cake
From Andrew Scrivani for the  The New York Times

Ingredients:

2 1/2 sticks unsalted butter, at room temperature, more to grease pans 

1 1/2 pounds rhubarb, rinsed and sliced into 1/2-inch cubes (about 4 cups) 

2 teaspoons cornstarch 

1 1/2 cups granulated sugar 1/2 cup light brown sugar 

2 cups cake flour 

1 1/4 teaspoons baking powder 

1/2 teaspoon fine sea salt 

Zest of 1 lemon, grated 

1 teaspoon vanilla extract 

4 large eggs 

1/3 cup sour cream 

2 teaspoons lemon juice

Method:
Preheat oven to 325.
Line the bottom of a 9-inch springform pan with parchment paper. Butter the paper and sides of the pan. Wrap two layers of foil under the pan, and place it on a buttered baking sheet. 

In a bowl, mix the rhubarb, cornstarch and 1/2 cup of the sugar.

In a small skillet, mix the brown sugar and 1/2 a stick of butter. Place over medium heat and stir until smooth and bubbling.

In another bowl, sift the cake flour, baking powder and salt and set aside.

In a mixer with a paddle attachment, beat the 2 sticks of butter until light. Add the 1 cup of sugar and the lemon zest. Cream until light and fluffly, scraping down the sides often.

Add the vanilla and eggs, one at a time. Then beat in the sour cream and lemon juice. It will look curdled at this point.
On low, add the flour mixture 1/3 cup at a time until mixed in, scraping the sides of the bowl often.

Pour the brown sugar mixture into your prepared springform pan, the  add the rhubarb. Pour the batter over everything, smoothing it over.
Bake for 1 hour and 15 minutes or until a cake tester comes out clean.

Cool (with the foil turned down a bit) on a wire rack for only 15 minutes. Run a knife around the cake, place a plate on top and turn it upside down. This is when I removed the foil and released the springform sides carefully.