For the trout, season the trout fillets all over with salt and freshly ground black pepper.
Heat the butter in a frying pan over a medium to high heat. When the butter is foaming, add the trout fillets, skin-side down, and fry for 2-3 minutes, or until the skin is crisp and golden-brown and the flesh is almost cooked through.
Turn the trout fillets over and fry for a further minute, then remove the pan from the heat and set aside to rest (the residual heat from the pan will cook the trout fillets through).
Meanwhile, for the dwarf beans, peas and almonds, add 25g/1oz of the butter and all of the beans to a frying pan and heat over a medium heat. Pour in enough boiling water to just cover the beans, then return to the boil.
Reduce the heat until the mixture is simmering, then continue to simmer for 2-3 minutes, or until the beans are just tender. Drain well and set aside.
Add the peas and continue to boil for a further 1-2 minutes, or until tender.
Meanwhile, heat the remaining butter in a separate frying pan over a medium heat. When the butter is foaming, add the shallots and fry for 3-4 minutes, stirring frequently to prevent the shallots from sticking or burning, until the shallots have softened and are golden-brown and the butter has darkened in colour.
Add the drained beans and peas and the flaked almonds to the pan with the shallots in it and stir to combine. Season, to taste, with salt and freshly ground black pepper.
Meanwhile, for the salad and dressing, heat the two tablespoons of light olive oil in a frying pan over a medium heat. When the oil is hot, add the bread cubes and fry for 1-2 minutes on all sides, or until crisp and golden-brown all over. Remove the croûtons from the pan using a slotted spoon and set aside to drain on kitchen paper. Season, to taste, with salt.
In a large bowl, whisk together the mustard, vinegar and the two tablespoons of extra virgin olive oil until well combined. Add the lettuce leaves and croûtons and mix with the dressing until they are coated.
To serve, spoon the dwarf beans, peas and almonds into the centre of each of four serving plates. Place two fillets of trout on top of each serving. Pile the salad alongside.