Mix rice, salt and boiling water in big saucepan. Cover and simmer for 20m minutes. Remove and let cool.
Remove spinach shanks, rince and strain. Simmer on medium saucepan for 3 minutes. Rince with cold water immediately after and spin-dry. (Frozen spinach should be prepared accordingly to the directions on the package, strained and spin-dried).
Put all ingredients in large bowl and mix well. Pour mixture in a 20 X 30 X 5 greased plate.
Bake at 350 F (180 C) for 35 to 45 minutes until golden.