Finnish Onion Pie (SIPULIPIIRAKKA)

In large bowl, dissolve yeast in warm water. Let stand 5 minutes. Add salt,oil or butter, and flour. Beat until dough is smooth and satiny.
Cover, let rise for 1 hour (until doubled).

 
Cut onions into thin slices(a food processor or mandolin is good for this).
Place onions in frying pan along with ham and cook over low heat until onions are
soft (about 15 minutes). Remove from heat, stir in sour cream, eggs, salt
and caraway seeds. Butter 10 inch pie,quiche or tart pan.
Preheat oven to 400 degrees F.
On lightly floured board, roll out pastry to fit prepared pan. Place pastry into pan and trim edges or flute. Turn filling into lined pan. Bake for 35 to 40 minutes
until crust is browned and filling is set.