(2 sticks) butter,softened
squares unsweetened chocolate,melted
1Preheat oven to 350. Coat two loaf pans with cooking spray and dust with flour;tap out excess flour.
2Combine flour,sugar,baking powder and baking soda in large mixing bowl. Add butter and beat with an electric mixer on low speed,scraping sides of bowl often,until mixture looks like moist crumbs.
3Beat in yogurt,eggs and vanilla on low speed until blended.Now, beat on high speed until batter is very light and fluffy.
4Pour half of batter into another bowl and stir in melted chocolate.Spoon white and chocolate batters alternately into prepared pans.
5Bake 45-55 minutes or toothpick comes out clean.Remove from oven and cool for 15 minutes.Run knife around edges to loosen cakes and cool on wire racks.