Mix sauce. Crack an egg into a small mixing bowl, grate parmesan cheese into bowl, add a bit of hot gnocchi water, and lemon juice to egg. Whisk until all incorporated. Set aside.
Save 1 cup of remaining gnocchi water, and set aside. Add gnocchi to meat in skillet. Spread gnocchi out into a single layer on pan. Cook until gnocchi is browned on at least one side.
Remove pan from heat then add egg mixture. Stir. Add gnocchi water a bit at a time to thin out the sauce. Return to low heat, simmer until sauce is desired thickness.