Into a medium-size mixing bowl, add vegan mayonnaise, celery, red onion. garlic powder, seafood seasoning, and cayenne pepper sauce. Stir to combine.
Fold in the hearts of palm and vegan cheddar cheese.
Onto each of the toasted English muffin halves, add the hearts of palm mixture in an even layer.
Arrange onto a baking sheet and set under the broiler. Allow broiling just until cheese is melted.
Garnish with dill and serve hot.