In a large bowl, beat the oil and sugar until smooth, 1 to 2 minutes. Mix in the egg whites and vanilla. With a wooden spoon, stir in the flour mixture until just combined.
Fold in the prunes, peanuts and morsels.
Spread the batter in the pan. Bake 25 to 30 minutes or until a wooden pick inserted in the center comes out clean or with moist-looking crumbs. Cool 5 minutes in the pan, then turn out onto a wire rack to cool completely. Cut into 12 pieces and store in an airtight container for up to 5 days.
Nutrition information per serving:
Calories from Fat: 72
Trans fats: 0g
Carbohydrate: 19 g