crust

1 c. flour

1 stick butter

1/4 t. salt

1 T sugar

1T lemon zest

filling

1 c. ricotta cheese

juice of 1 lemon

zest from peel of one lemon

1/4 c. sugar

1 egg yolk (optional)

assemble crust.  mix together filling.  bake in 350 degree oven for one half hour to forty five minutes.