Preheat the oven to 325°F. Spray a 1/2-quart baking dish with non-stick cooking spray.
In a medium bowl, stir together the cream cheese, sour cream, mayonnaise, lemon juice, Worcestershire sauce, dry mustard, garlic powder, and 1/2 cup cheddar cheese.
Fold in the hearts of palm. Add Old Bay seasoning and cayenne pepper sauce, adjusting the amount to taste.
Transfer to the prepared baking dish. Top with the remaining 1/4 cup cheddar cheese. Bake 30 minutes, or until bubbly and lightly golden brown. Allow the dip to set for 10 minutes, until no longer bubbling, then serve hot.