01 -
Get your skillet or sandwich maker hot by preheating it over medium-high heat.
02 -
Put one slice of cheese on a piece of bread. Lay the avocado slices over the cheese, making sure the edges of the cheese are still visible.
03 -
Layer the second slice of cheese on top of the avocado, followed by the bacon, and then cover everything with the second piece of bread.
04 -
Stir together the butter and mayo until smooth, then spread half of it on the top slice of bread.
05 -
Put the sandwich, buttered side facing down, into the sandwich maker. Spread the rest of the mixture on the top, close the lid, and cook for 2 to 5 minutes until golden and melty. Use tongs or a spatula to take it out, slice it in half, and enjoy immediately.
06 -
Place the sandwich butter-side down in your hot skillet. Spread the remaining butter mixture on the unbuttered side. Let it cook for 3 minutes, flip it, and cook another 2 minutes while pressing gently with a spatula or grill press. Add a dab of butter if the bread feels dry, and cook until golden and cheesy.