Gather all necessary ingredients: 2 slices of bread, 1 ripe avocado, 2 tablespoons of butter, 2 slices of cheddar cheese, 1 teaspoon of lemon juice, 1/4 teaspoon of garlic powder, 1/4 teaspoon of salt, and 1/4 teaspoon of black pepper.

Cut the ripe avocado in half, remove the pit, and scoop the flesh into a medium bowl. Mash it until smooth and mix in lemon juice, garlic powder, salt, and black pepper.

Set the avocado mixture aside to allow flavors to meld.

Heat a frying pan or griddle on medium for 2-3 minutes.

Spread butter on one side of each slice of bread.

Place one slice of bread in the pan, buttered side down. Add a slice of cheddar cheese, then top with another slice of bread, buttered side up.

Grill for 3-4 minutes until golden brown, then flip and grill the other side for another 3-4 minutes.

Remove from pan, let cool for a minute, slice in half, and spread the mashed avocado.