Pistachio chocolate swirl brownies

1. Preheat oven to 350°F.
2. Butteri a 9x13" pan. Melt chocolate; set aside to cool.
3. In large bowl, beat together butter, sugar and vanilla until light and fluffy.
4. Beat in eggs, one at a time.
5. Blend in flour and salt.
6. Divide batter in half.
7. To one half, add almond extract, chopped pistachios, and enough green food color to tint batter a light green (2-4 drops).
8. To other half of batter, stir in melted chocolate and chocolate chips; mix well.
9. Spoon batter alternately into pan, checkerboard fashion.
10. Swirl batters to get a marbled effect.
11. Bakei for 45 minutes or until tested done.
12. Cool completely; cut into bars.