Pre-heat the oven to 220°c and place the tomatoes and mushrooms on a non-stick baking tray.
Drizzle with the olive oil, balsamic and garlic and season to taste.
Roast for 15-20 minutes until the vegetables are soft and starting to caramelise.
When the tomatoes and mushrooms are cooked, remove from the oven and allow to cool slightly.
To assemble the sandwich, generously spread the slices of bread with mayo then top with the baby spinach, tomatoes, bacon, mushrooms and finally the fried egg.
Add the remaining slices of bread then serve immediately.