1Heat oven to 400°F. In medium bowl, beat butter and brown sugar with electric mixer on low speed until fluffy. Beat in egg product until blended. Beat in flour until dough forms. Press dough firmly in bottom and up side of ungreased 9-inch tart pan with removable bottom. Prick bottom thoroughly with fork.
2Bake 10 to 12 minutes or until light golden brown. If crust puffs in center, prick with fork. Cool 30 minutes or until completely cooled.
3In small bowl, beat lemon curd and sour cream with wire whisk until smooth. Spread evenly over crust. Refrigerate at least 1 hour. Just before serving, top with blueberries.