Preheat oven to 350°. Spray 12 (2½-inch) standard-size muffin cups with nonstick spray; set aside.

Whisk together eggs, creme friache, dill, horseradish, salt, and pepper in large bowl. Stir in salmon, mozzarella cheese, and ¼ cup green onions.

Pour egg mixture evenly into prepared muffin cups. Bake 24 to 26 minutes or until eggs are set along edges and internal temperature reaches 165°. Cool in muffin cups for 10 minutes. Loosen from cups with a knife; remove egg muffins from muffin cups.

Serve warm or store in airtight container in refrigerator for up to 1 week. To reheat, microwave on HIGH for 20 to 25 seconds before serving.