In a medium bowl, combine cheeses, pimientos, mayonnaise, pecans, dill pickle relish, sugar, garlic powder, and pepper, stirring to combine well.
Using a serrated knife, cut a thin slice off bottoms of tomatoes to create a level base. Cut tops from tomatoes. Using a melon baller, remove pulp, leaving shells intact. Turn tomatoes upside down on paper towels to drain for 10 minutes. To serve, spoon pimiento cheese into tomato shells.
Recipe by Southern Lady Magazine at https://southernladymagazine.com/pimiento-cheese-stuffed-tomatoes/