For the trout tartare:
Carefully fillet the trout, coaxing the flesh into a delicate, finely diced tartare. Season gently with salt, extra virgin olive oil, finely minced parsley, and a few drops of fresh lemon juice, then set aside to harmonize.

For the trout nectar (sauce):
Slowly toast the fish bones in the oven at 130 °C for 3 hours, drawing out their deep, roasted essence. Transfer them to a pot with 1 liter of pure water, bring to a boil, and let simmer for 1 hour to concentrate the flavors. Blend the mixture thoroughly, strain precisely to capture 1 liter of rich broth. Stir in 14 g of ruby red miso and set aside; this precious jus will envelope the spaghetti in its final moments of cooking.

For the yeast dust:
Expose the brewer's yeast to the heat of the oven at 160 °C until its moisture is entirely surrendered. Finely chop with a knife to fashion a textured, artisanal dust of irregular character.

For the emerald parsley oil:
Pluck the parsley leaves, blanch them in boiling water for 3 minutes to lock in their vibrant green hue, then plunge immediately into ice-cold water. Blend in the Thermomix with extra virgin olive oil at 60 °C for 10 minutes at maximum velocity. Carefully strain the resulting elixir and preserve.

For the garlic infusion:
Pour the extra virgin olive oil into a small saucepan, cradling the two halves of the garlic head. Confis gently over low heat until the garlic blushes with a delicate golden hue. Withdraw from the flame and let the garlic steep in the oil for 24 hours at room temperature, imparting its fragrant soul. Once the infusion is complete, filter the oil and discard the bulb.

For the spaghetti:
Boil the spaghetti for 3 minutes in salted water. Complete its cooking directly in the trout sauce, enriched with butter, extra virgin olive oil, garlic-infused oil, a few bright droplets of lime juice, and the savory depth of anchovy colatura. Toss with grace until the pasta is draped in a rich, velvety cream.

For the presentation:
Grace the base of the dish with a bed of the seasoned trout tartare. Nestled atop, place the beautifully creamed spaghetti, and crown this culinary canvas with trout roe, a scattering of yeast dust, and a final drizzle of parsley oil.