Preheat oven to 450°F. Prepare crusts as directed on package. Place in two 9-inch tart pans with removable bottoms; mold crusts to fit sides of pans. Pierce crusts with fork. Bake 8 to 10 minutes or until lightly browned. Reduce oven temperature to 400°F.
Meanwhile, mix cream cheese, Italian seasoning, onion powder and red pepper in large bowl until well blended. Add artichokes, spinach and grated cheese; mix well. Divide mixture in half. Spread evenly in crusts.
Bake 10 minutes or until cheese is melted. Cool 5 minutes. To serve, remove sides of pans. Cut tarts into thin wedges. Serve warm or at room temperature.