1/2 c. butter, softened
1/3 c. sugar
1 1/4 c. flour
1/2 c. pistachio nuts, chopped
1 (7 oz.) jar marshmallow creme
1 c. sour cream
3 tbsp. lime juice
1 tsp. grated lime peel
3 c. Cool Whip

Beat together butter and sugar. Add flour, mix well. Press into a 9-inch tart pan with removable bottom. Bake 12-15 minutes, until light brown. Cool.

Mix together marshmallow creme, sour cream, lime juice, lime peel and 1/2 of nuts. Fold in Cool Whip.

Sprinkle the remaining nuts on crust; add the mixture. Refrigerate.