Preheat a sauté pan. Use 1 tbsp of butter to spread over the slices of bread and place on the pan. Toast the bread for 2 minutes on each sides or until toasted and warmed on both sides. keep aside.
In the meantime, in a sauté pan over high heat, add the pancetta pieces and sauté for 1 minute.
Add 1 tbsp of butter, the garlic, mushrooms, herbs. Season generously with pepper and a little of salt. Sauté́ for 2-3 minutes until coloured.
Add the smoked trout pieces, the cream and crumble enough blue cheese to your preference. Stir and simmer for a further minute or so.
Remove from the heat and add the last tablespoon of butter. stir to ‘Monter au beurre’ and create a shinny sauce.
To serve, arrange the toasted bread on warmed serving plates and spoon the pancetta and mushroom mixture on top.
Serve immediately.