Preheat your oven to 220 °C/200 °C fan/gas mark 7. Bring a large saucepan of water to the boil with 1/2 tsp salt.
Lay two slices of Serrano ham lengthways on a board. Place a chicken fillet horizontally across the middle, then wrap the ham around the chicken to enclose it.
Repeat with the remaining chicken and ham, then place them seam-side down on a lightly oiled baking tray.
Drizzle with a little oil, then roast on the middle shelf of your oven until cooked through, 25-30 mins. IMPORTANT: Wash your hands and equipment after handling raw chicken and its packaging. The chicken is cooked when no longer pink in the middle.

Meanwhile, pick the tarragon leaves from their stalks (discard the stalks).

Halve the tomatoes. Zest and halve the lemon. Peel and grate the garlic (or use a garlic press). Set aside a quarter of the rocket for garnishing later on.

To make your pesto, pop the remaining rocket, tarragon leaves, walnuts, lemon zest and juice into a food processor and blend until well combined

If you don't have a food processor, finely chop everything instead and combine with the lemon juice in a small bowl.

Bring a large saucepan of water to the boil with 1/2 tsp salt.

When the 10 mins of roasting time remain, add the tomatoes to the chicken's baking tray. Drizzle with olive oil and season with salt and pepper.
Roast for the remaining time until the tomatoes have softened and the chicken is cooked, 8-10 mins. IMPORTANT: The chicken is cooked when it is no longer pink in the middle.
Once cooked, transfer the chicken to a board. Cover and allow to rest, 3-4 mins.

Meanwhile, add the tagliatelle to the pan of boiling water and bring back to the boil. Cook until tender, 3-4 mins.
Once cooked, reserve some pasta water (see pantry for amount) for the sauce, then drain in a colander.
Pop back in the pan, drizzle with oil and stir through to stop it sticking together.

Meanwhile, heat a drizzle of oil in a medium frying pan on medium heat.
Once hot, add the garlic and stir-fry for 1 min, then pour in the reserved pasta water and chicken stock paste.
Bring to the boil and simmer until reduced by half, 4-5 mins.
Reduce the heat to low, then add your tarragon pesto and the butter. Stir vigorously until the butter has melted and everything is well combined, then remove from the heat.

Taste the sauce and season with salt, pepper and lemon juice if needed, then add the cooked tagliatelle to the pan and toss to coat.
Once rested, cut the chicken widthways into 2cm slices.
Share the tagliatelle between your plates and top with the sliced chicken and roasted tomatoes.
Garnish with the remaining rocket to finish.
Enjoy!