Preheat your oven or broiler to 250 C.

Put two slices of bread on the cooky sheet, spread mayo on both slices, on one slice, place tomato slices evenly, then the basil, then the cheese, dribble about 1/2 teaspoon of olive oil on the tomato slice, add a pinch of salt and pepper. Leave the other slice on the side and put in the oven or broiler for 30 seconds or so to melt the cheese. Then add the plain side to the tomato side and drizzle another 1.2 teaspoon of olive oil over that, back in the oven or broiler for about a minute until the top slice is toasted, remove from the oven or broiler, flip sandwich, drizzle the rest of the olive oil and cook again for about 1 minute. Serve.