MIXED BERRY GALETTE

3 cups mixed berries (I used blackberries, blueberries, raspberries and strawberries)
3/4 - 1 cup of sugar or splenda depending on tartness of berries
3 pea sized pieces of butter
1 egg
1 - 9 inch ready made pie crust

Mix berries and sugar in bowl. Place pie crust on parchment and roll out a little. Place parchment with crust on baking sheet. Put berry mixture in center of crust leaving about an inch border. Place pieces of butter on top of berries. Fold up the border of crust over berry mixture. Brush crust with egg wash. Bake at 425 degrees until crust is golden brown. Serve with vanilla ice cream or whipped cream.