1 1/4 c. shelled pistachios, divided
1/4 c. brown sugar
1/4 c. water
6 oz. white chocolate, coarsely chopped
1 c. butter
3/4 c. sugar
1 Tbsp. corn syrup
Heat oven to 350°. Place pistachios in single layer in pan; toast for three minutes. Remove from oven, cool and coarsely chop; set aside. In heavy saucepan combine butter, sugars, water and corn syrup. Bring to boil over medium-high heat, stirring constantly with wooden spoon. Reduce heat to medium and continue to boil until mixture reaches 300° (hard crack stage, use candy thermometer), stirring frequently. Stir in 3/4 cup pistachios; mix well and pour into jellyroll pan lined with buttered foil. Spread mixture into large rectangle. Cool completely. In microwave-safe container microwave white chocolate 30 seconds; stir. Continue microwaving in 10-second intervals, stirring after each, until chocolate is melted and smooth but not hot. Using spatula spread over toffee, covering it completely. Sprinkle with remaining 1/2 cup pistachios and gently pat into chocolate. Place pan in refrigerator for five minutes or until chocolate has set. Break into pieces and store in airtight container for up to one week.