Make the filling: Bring the cream and coffee nearly to a boil in a saucepan over medium heat. Reduce the heat to low; cook for 5 minutes. Remove from the heat. Strain through a fine-mesh strainer into a bowl. Set aside.
Bring the caramel topping to a boil in a saucepan over medium-high heat. Reduce the heat to medium and cook for 2 more minutes. Remove from the heat and stir in the butter. Slowly whisk in the cream-coffee mixture until combined. Pour into a large bowl and cool to room temperature. Refrigerate for 45 minutes, or until completely chilled.
Make the cups: Place the pastry shells on an ungreased baking sheet and bake according to the package directions. Transfer to a rack to cool, then pull out the center of the shells with your fingers.
Place the chocolate chips in a small microwave-safe bowl and microwave on medium power, stirring every 30 seconds, until melted, about 1 1/2 minutes. Pour the toffee bits into a pie plate. Dip the rims of the pastry shells in melted chocolate and then in the toffee. Set aside.
Beat the coffee mixture with a mixer on medium speed until thickened. Slowly beat in the confectioners' sugar on high until stiff peaks form.
Assemble the cups right before serving or selling: Spoon the coffee mixture into a large zip-top plastic bag. Press out the air and seal. Snip off a corner; pipe the mixture into the shells. Drizzle with more caramel.
Photograph by Antonis Achilleos
Recipe courtesy Sandra Lee's Bake Sale Cookbook for Food Network Magazine