Step 1

Stir together 3/4 cup creme fraiche, the chive blossoms, chives, and lemon juice to taste. Season with salt.

Step 2

Bring a large pot of salted water to a boil, and cook pasta until al dente. Drain, reserving 3/4 cup pasta water. Toss pasta with butter and creme fraiche mixture, adding enough pasta water to make a light sauce. Season with salt and pepper.

Step 3

Place a small dollop of remaining creme fraiche in each of 4 to 6 dishes, and sprinkle with chive blossoms and chives. Divide pasta among dishes. Top with caviar and more creme fraiche. Press egg white and yolk through a sieve, then sprinkle over pasta. Serve immediately.