-
Make the Cake: Preheat oven to 350 degrees; butter and flour two 6-inch round cake pans. Set aside.
-
In the bowl of an electric mixer fitted with the paddle attachment, cream together butter and sugar. Add eggs, one at a time, mixing well after each addition.
-
In a large bowl, whisk together flour, baking powder, and salt. Add flour mixture to butter mixture, alternating with milk, mixing well after each addition. Stir in lemon zest.
-
Place 2 3/4 cups batter in each prepared cake pan. Transfer to oven and bake until a cake tester inserted into the centers comes out clean, 45 to 50 minutes. Remove from oven and let cool slightly in pans; invert cake onto a wire rack.
-
Make the Glaze: In a small bowl, mix together Cognac, lemon juice, and sugar until sugar is dissolved. Brush glaze over cake and let cool completely. Serve with candied lemon slices and kumquats.