Bring the water to a boil in a large saucepan. Add the shrimp and cook just until done. Drain and cool slightly. Chop shrimp finely and refrigerate (The shrimp can be chopped by hand, or in a food processor using an on/off method just until chopped). Melt butter in a large skillet over low heat. Add celery and cook until soft, about 10 minutes. Reserve pan for final cooking of shrimp cakes.
In a large mixing bowl, combine celery, saltine cracker crumbs, cayenne pepper, eggs, mayonnaise, salt, pepper and chopped shrimp. Mix well. If the mixture does not hold a shape, add a small amount of bread crumbs (1/4 - 1/2 cup). Shape into 16 small cakes. Refrigerate the shrimp cakes for at least 30 minutes. Prior to cooking, evenly coat the cakes with bread crumbs.
In the large skillet, add vegetable oil to remaining butter, approximately 1/2 inch in depth. Heat to medium high and cook the shrimp cakes, a few at a time until golden brown (6-8 minutes total). Transfer to paper towels and drain. Serve immediately with avocado butter and red pepper cream. 6 servings.