Squash, onions, chilies, lemon juice, salt together.
Add the tuna into the mixture and then the pepper and finally the mayonnaise and mix well.
Lightly butter the bread slices, spread about 1 tablespoon of the tuna mixture on one slice, and cover with another.
If you would like to toast the sandwich, it would be better to leave out the mayonnaise.
Serving Size 4 Servings