For pastry: In a large mixing bowl, beat together cream cheese and 1/2 cup butter with an electric mixer on medium to high until smooth. Add 1-1/2 cups flour and beat on low speed until combined. Cover and chill for at least 1 hour or until dough is easy to handle.

Meanwhile, clean mushrooms. Place morel mushrooms, if using, in a large bowl. Cover with cold tap water; add 1/2 teaspoon salt. Soak for 10 to 15 minutes. Drain, rinse and repeat two more times. Drain thoroughly; pat mushrooms dry with paper towels. Chop mushrooms (you should have 2 cups).

For filling: In a large skillet, cook onion in 3 tablespoons butter over medium heat until tender. Add mushrooms. Cook and stir for 3 to 5 minutes or until liquid is nearly evaporated. Remove from heat.

In a small bowl, stir together sour cream, 2 tablespoons flour, 1/4 teaspoon salt, marjoram, and rosemary until combined. Stir sour cream mixture into mushroom mixture.

On a floured surface, use your hands to slightly flatten the dough. Roll dough from center to edges to 1/8-inch thickness. Cut dough into twenty-four 3-inch circles, rerolling dough as necessary. Using small cutters, make cutouts in the centers of half of the rounds or cut a slit in half of the rounds to let the steam escape during baking.

Place 12 of the circles, without cutouts, on an ungreased baking sheet. Place about 1 tablespoon of the filling in the center of each. Moisten edges of filled pastry with a little water. Add the remaining 12 circles with cutouts or slits. Crimp edges together with a fork. Brush tops with beaten egg.

Bake in a 350 degree F oven 25 minutes or until pastry is golden brown. Serve warm. Makes about 12 appetizer servings.

Cool the baked pastries, then wrap and freeze up to 1 month. To serve, place frozen pastries on an ungreased baking sheet. Bake, uncovered, in a 350 degree F oven for 20 minutes or until heated through.