In a medium bowl, mix together cheeses, mayonnaise, pimentos with liquid, garlic and onion powders, salt and pepper.
Heat up griddle or skillet on the stove top to a medium-low heat.
Butter one side of each slice of bread.
Place one slice of bread in skillet, butter side down. Spoon pimento cheese on top. Let cook until cheese begins to melt and bottom of bread turns golden brown.
Top with 3 bacon slices and 1 apple slice. Add second slice of bread, buttered side up.
Using a spatula, gently turn sandwich over. Brown second piece of bread to a golden brown and let cheese continue to melt.
Remove from skillet and serve.
Notes
Grilled cheese sandwiches cook best on slowly on low heat. This lets the cheese melt without over toasting the bread.