Sift together flour, baking powder, salt and cayenne pepper into a mixing bowl. Add shortening and cut in with a pastry blender until well incorporated. (I think you could do this with a few pulses in a food processor.) Stir in Cheddar cheese, onion, and Worcestershire and Tabasco sauces. Add buttermilk and stir to make a soft dough.
Wrap in wax paper or plastic wrap and chill for 1 hour.
Preheat oven to 475°F
On a lightly floured board, roll out dough into an 8-x 12-inch rectangle. Wrap loosely around rolling pin and transfer to a cold lightly greased baking sheet. With a metal spatula, cut dough in half lengthwise, then cut across at 1-inch intervals to form the sticks. Brush sticks with melted butter, sprinkle with Parmesan and bake until lightly browned, about 10 minutes.
Immediately remove from baking sheet and serve hot, or cool on wire racks before storing in airtight containers.