Preheat oven to 400 degrees and lightly grease a 1-1/2 quart baking dish.
Peel fresh peaches with a vegetable peeler and slice into medium-size bowl. Add berries, then brown sugar, flour, and ginger; toss to coat. Stir in Grand Marnier, if using. Bake for about 10 minutes.
1-1/2 cups flour
1/2 cup quick oats
1 tbsp. baking powder
1/2 tsp. cinnamon
1/3 cup sugar
1 egg, lightly beaten
1/3 cup milk
1/3 cup melted butter
Cinnamon sugar for sprinkling
While fruit is heating up, combine dry ingredients of oatmeal biscuit mix in medium bowl. Add beaten egg, milk, and melted butter, stirring just until moist. Do not over mix! (Note: If you have extra biscuit dough, bake them by the spoonful separately for a wonderful snack!)
Sprinkle lightly with cinnamon sugar. Bake for about 15 minutes or until biscuits are lightly golden.
Serve warm with fresh whipped cream or vanilla ice cream.