The "triple" in this recipe comes from citrus in the batter, citrus syrup brushed over the warm cake, and a finishing touch of citrus glaze just for fun!
Cake: Preheat oven to 350 degrees. Coat a 10-cup Bundt pan (or kugelhopf mold) with cooking spray; dust with flour, tapping out excess. Finely grate 2 teaspoons lemon zest and 1/2 teaspoon orange zest.
With a sharp knife, remove peel and bitter white pith from all citrus. Holding a lemon over a bowl, cut between membranes to release segments into bowl. Squeeze juice from membranes into another bowl. Repeat with remaining lemon and orange(s), combining segments in one bowl and juices in other. Cut segments into 1/4-inch pieces. (You will need 3 tablespoons juice and 3/4 cup segments.)
Sift together flour, superfine sugar, baking powder, and salt into a bowl. Add creme fraiche; beat on medium speed until combined. Add eggs, one at a time, beating to combine after each. Beat in butter, citrus juices, and zests. Add citrus segments and beat just to combine. Transfer batter to prepared pan. Bake, rotating pan once, until a tester inserted in middle comes out clean, about 48 minutes.
Syrup: Bring citrus juices and superfine sugar to a boil in a saucepan, stirring until sugar is dissolved. Boil 30 seconds more.
Glaze: Whisk together confectioners' sugar and lemon juice in a bowl.
Serving: When cake is done, leave oven on and let cake cool in pan on a wire rack set on a baking sheet 15 minutes. Turn out onto rack and let cool 10 minutes more. Transfer to a shallow dish. Brush syrup over cake. Continue brushing syrup from dish until all syrup is used. Return cake to wire rack; let dry in oven 5 minutes. Immediately brush with glaze. Let cool completely. Cake can be stored, covered, up to 1 day.
Spoon whipped cream into center of cake; top with candied zest and serve.