1. Preheat oven to 375°F. Heat a small skillet on medium heat. Add mustard and fennel seeds; cook and stir about 2 minutes or until fragrant. Immediately pour out of hot pan to avoid over-toasting. Finely crush seeds using a small food processor, a clean coffee grinder, a rolling pin or a mortar and pestle. Pour into small bowl. Stir in hot water. Let stand 5 minutes.
2. Mix eggs, milk, pepper and seed mixture in medium bowl with wire whisk.
3. Heat oil in large nonstick ovenproof skillet n medium heat. Add potatoes; cook and stir 5 minutes or until lightly browned. Slowly pour in egg mixture. Sprinkle salmon and green onions evenly over eggs. Cook 5 minutes without stirring or until eggs are just set on bottom. Transfer skillet to oven. Bake 5 to 7 minutes or just until the eggs are set. Cut into wedges to serve. Serve with sour cream, if desired.