Preheat oven to 400. Using an electric mixer with paddle attachment or a food processor with a metal blade, mix 1 cup sugar and flour together. Add coarsely chopped anise and cold butter. Mix just until large pea size chunks form and crumbs hold together when a handful is squeezed. Set aside.

Trim ends of rhubarb, cut into 1 inch lengths, and toss with lemon juice, orange zest, vanilla and remaining sugar. Place in a 9 inch pie pan. Cover with sugar/anise topping. Bake for 45 minutes or until fruit juices are bubbling around the sides of the pan and the crisp is evenly golden.