To make the fritter batter, combine flour, baking powder and salt in a large bowl. In another smaller bowl, whisk together oil, milk, egg and black pepper. Add the egg mixture to the flour mixture and combine until all dry ingredients are moistened.
Heat oil to 375 degrees F in a deep-fryer.
Mix panko bread crumbs, Cajun Seasoning, mayonnaise, parsley and lemon juice. Fold in crab meat, trying to avoid breaking up lumps. Form crab mixture into "cocktail size" balls. Place the crab ball on a slotted spoon, and holding over the bowl of fritter batter, ladle enough of the batter over it to coat. Deep-fry in hot oil until golden brown and drain.
Whisk together mayonnaise and Chipotle Chile Powder. Season, with salt, if needed. Serve crab fritters with spicy mayo as a dipping sauce.