Put the mirliton in a saucepan and cover with water. Boil, uncovered, for 30 to 35 minutes, or until fork tender. Cool under tap water and drain thoroughly. Mash slightly with a fork and set aside.
Combine the eggs, salt, cayenne, and baking powder in a mixing bowl and mix well. Add the milk and whisk for a few seconds.
Beat in the flour, 1/4 cup at a time, until all of it is incorporated and the batter is smooth. Add the mirliton, onions, and bell peppers and mix well.
Heat at least 2 inches of the shortening in a large, deep-frying pan to 360ºF. Drop the batter, a tablespoon at a time, into the hot oil. When the fritters pop to the surface, roll them around in the oil using a long-handled spatula or tongs until they are evenly browned.
Drain on paper towels. Sprinkle with the rub and serve.
Yield: about 24