Make the Creole mustard sauce: in a small bowl combine 1/2 cup mayonnaise, 1/2 cup sour cream, 1/4 cup Creole mustard, 1 tablespoon honey, and 1/8 teaspoon cayenne pepper. Stir until smooth and refrigerate until needed.
Trim and cut 1 1/2 pounds cube steak into 1‑inch-wide strips (fingers). Pat the pieces dry and season lightly with salt and pepper.
Set up your breading station: place 1/2 cup flour on a plate. In a medium bowl whisk together 2 eggs (lightly beaten), 1/3 cup milk, and 1 teaspoon Worcestershire sauce. On another plate combine the remaining 1/2 cup flour, 1/2 sleeve finely crushed Saltine crackers, 2 teaspoons Cajun seasoning, and 1/2 teaspoon black pepper.
Pour about 2 inches of vegetable oil into a Dutch oven and heat the oil to 375°F.
Working one piece at a time, dredge a steak finger in the plain 1/2 cup flour, shaking off excess; dip it into the egg mixture; then press and coat it evenly with the flour/saltine/cracker mixture.
Fry the steak fingers in the hot oil in two batches (do not overcrowd the pot). Cook until golden brown on both sides and cooked through, about 6–8 minutes per batch, flipping as needed.
Transfer cooked steak fingers to a wire rack to drain while you fry the remaining pieces.
Serve the steak fingers with the refrigerated Creole mustard sauce.