1 (8 ounce) package cream cheese, softened
2/3 cup white sugar
2 teaspoons ground cinnamon
2 pounds large, fresh mushrooms, stems removed
2 tablespoons olive oil
1 2 cups chopped onion
3 tablespoons Worcestershire sauce
Rinse the mushrooms, place them in a colander, and rinse for several minutes. Add more water if necessary to rinse completely. Place mushrooms in a large nonporous bowl, keeping the water outside to prevent drying out.
In a small saucepan over medium heat, melt the butter, stirring constantly, until the butter is almost completely melted. Stir in the onions. Add Worcestershire sauce, and continue to cook until the onions are soft, about more than 1 hour.