Rhubarb Upside-Down Cake

• Vegetarian

• Produce

  • 1 Lemon, Zest of
  • 1 1/2 lbs Rhubarb

• Refrigerated

  • 4 Eggs, large

• Condiments

  • 2 tsp Lemon juice

• Baking & Spices

  • 1 1/4 tsp Baking powder
  • 1/2 cup Brown sugar, light
  • 2 cups Cake flour
  • 2 tsp Cornstarch
  • 1 1/2 cups Granulated sugar
  • 1/2 tsp Sea salt, fine
  • 1 tsp Vanilla extract

• Dairy

  • 2 1/2 sticks Butter, unsalted
  • 1/3 cup Sour cream

Found on cooking.nytimes.com