Prepare a grill for medium-high heat.
Brush some butter over the prawns and sprinkle with the seafood seasoning. Lightly oil the grill grates, then grill the prawns just until they turn opaque, being careful not to overcook.
Brush the buns with some butter. Grill until marked, about 2 minutes.
In a small bowl, stir together the cayenne and 1/4 cup of the mayonnaise. Spread on the buns.
In a large bowl, whisk together the pineapple, sugar, vinegar and the remaining 3/4 cup mayonnaise. Add the cabbage and jalapeno, and toss to coat. Add salt to taste.
Divide the slaw among the slider buns and then distribute the prawns among the buns. Serve.
This recipe was created by a contestant during a cooking competition. It has not been tested for home use.