Break spaghetti in half.
cook in boiling water until done, drain
while still warm combine spaghetti with eggs and parmesan.
pour into well greased 10 inch pie plate and pat mixture up and around sides with a spoon
melt butter, add onion, saute until limp
stir sour cream and spoon over spaghetti
remove sausage from casing, crumble and cook with hamburger until done
add tomato paste and water, simmer 10 minutes
spoon meat mixture on top of sour cream mixture
bake at 350 degrees for 25 minutes
arrange mozzarella on top and return to oven until cheese melts.