01 -
Warm a skillet over medium heat to ensure you'll get that perfect golden-brown crust on your sandwich.
02 -
Cut the avocado in half, remove the pit, and scoop the flesh into a bowl. Mash until smooth, then season with a pinch of salt and pepper.
03 -
In a separate bowl, combine the shredded mozzarella and cheddar cheese to create an even, melty blend.
04 -
Spread the softened butter on one side of each bread slice. Then spread mayonnaise on the unbuttered side of two slices.
05 -
Place the two bread slices with mayo-side-down in the warm skillet. Spread the mashed avocado evenly over them, then sprinkle with garlic powder and onion powder.
06 -
Sprinkle the cheese mixture generously over the avocado layer. Add fresh basil leaves on top of the cheese if using.
07 -
Top with the remaining bread slices, butter-side facing up.
08 -
Cook for 3-4 minutes per side, or until the bread turns golden brown and the cheese melts completely.
09 -
Remove from heat, let cool slightly for a minute, then slice diagonally and serve warm. Pairs wonderfully with tomato soup or a fresh salad!