Heat oven to 325ºF. Heat taco shells as directed on box. Meanwhile, in large bowl, gently mix fruit.
Carefully remove cardboard from ice cream (do not damage cardboard). With serrated knife, cut ice cream into 6 (4x1x1-inch) rectangles. (Reassemble box around remaining ice cream for freezer storage; if necessary, wrap carton in plastic wrap to secure.)
Place 1 rectangle of ice cream in bottom of each taco shell. Divide fruit mixture evenly over ice cream. Drizzle chocolate topping evenly over fruit. Top with whipped cream and nuts. Serve immediately.
The ice cream rectangles (or log shapes) are easy to cut. Slice two 1-inch-wide slabs crosswise from one end of ice cream brick, then cut the slabs lengthwise into thirds.
