Heat a water bath to 62C/144F. Place the whole eggs into the water bath and cook for 1 hour 15 minutes. If not using a water bath, simply poach the eggs as normal.
Peel the eggs and carefully slide them into a bowl of warm water. The eggs should hold together and be jelly-like. (If not using immediately, remove the egg in its shell from the water bath and carefully place into a bowl of ice-water. Once cooled, chill in the fridge until ready to use. Reheat it in the water bath for 5-8 minutes.)
Preheat the oven to 170C/325F/Gas 3. Lay the bacon between two heavy baking trays and bake for around 12 minutes or until crisp. Keep warm until ready to serve.
Heat a frying pan until hot, add half the butter and heat until foaming. Add the diced bread and cook until golden-brown all over, then tip out onto kitchen paper and cool.
Add the remaining butter to the pan with the trompette de mort and cook until just tender, about two minutes. Drain onto kitchen paper.
For the tomato fondue, heat a large frying pan until hot, add 3 tablespoons olive oil, shallot, garlic, thyme and bay leaves and cook gently until everything has softened. Add the tomato purée and cook for 2-3 minutes.
Reserve one third of the chopped tomaotes. Add the remaining tomatoes to the pan and cook for 6-7 minutes until the tomatoes have broken down and are nearly dry.
Place the mixture into a food processor and blend to a fine purée. Strain the mixture through a sieve into a clean pan and stir in the reserved tomatoes.
Whisk the mustard, vinegar and remaining olive oil together then stir into the tomatoes, to taste.
For the mushroom velouté, heat a sauté pan until hot, add the butter and heat until foaming.
Add the mushrooms, thyme and garlic and cook until golden-brown. Add the cream and cook until reduced and thickened.
Place into a food processor, blend until smooth then strain through a sieve into a clean pan. Season, to taste, with salt and freshly ground black pepper.
To serve, place a spoonful of the tomato fondue on one side of a soup plate, and a spoonful of the mushroom veloute on the other side. Pile the trompette de mort in the centre and scatter croutons and parsley around the plate. Place the egg on top of the trompette de mort and finish with a couple of pieces of crispy bacon.