1. In a small bowl, whisk together the whole eggs and yolks. In a stand mixer with the paddle mix the sugar, lemon zest and salt on low until fragrant, 30 seconds. Add cream cheese and beat on medium-low until no lumps, 2 to 3 minutes, scraping a few times. On low, slowly add the beaten eggs in 4 additions, scraping bowl and mixing to incorporate, 15 to 20 seconds each, On low, add the crème fraîche by spoonfulls Detach bowl and stir with a silicone spatula. Chill minimum 6 hours.
2. 02
Heat oven to 450 F. Cut a 14- to 15-inch parchment round and line a 9-inch springform pan, pushing the paper into the edges and against the sides of the pan, allowing it to form folds and pleats; set aside.
3. 03
Pour cold batter into the prepared pan; spread to level and tap away bubbles. Bake on center rack until deeply browned and center at 150°F to 155°F, 40 to 55 minutes; Temperature rises quickly so check every 3 to 4 minutes. Even when done, the center of the cake will jiggle when the pan is gently shaken. Transfer to a wire rack and cool for 1 to 2 hours; the cake will deflate as it cools.
4. 04
Refrigerate 4 hours, uncovered until chilled. Stand at room temp for about 30 minutes before serving. To serve, remove the sides of the pan, then set the cake, still on the springform base, on a platter. Pull the parchment away from the sides of the cake and cut the cake into slices.
