Preheat your oven to 220°C/200°C fan/gas mark 7. Pop a large saucepan of water on to boil on high heat.
Heat a drizzle of oil in a frying pan on medium-high heat. Once hot, lay the chicken in the pan, skin-side down. Season with salt and pepper.
Fry until the skin is golden, 5-6 mins, then turn and cook for 1 min on the other side. TIP: To ensure crispy skin, don't move the chicken. IMPORTANT: Wash your hands and equipment after handling raw chicken and its packaging.

While the chicken cooks, trim the carrots, then halve lengthways (no need to peel). Chop into roughly 1cm wide, 5cm long batons.
Put the carrot batons on a large baking tray. Drizzle with oil, season with salt and pepper, then sprinkle over the sugar for the carrots (see ingredients for amount). Toss to coat, then arrange in a single layer.
Pop the garlic (unpeeled) into a small piece of foil with a drizzle of oil and scrunch to enclose it.

Transfer the chicken to another baking tray, skin-side up.
When the oven is hot, roast the chicken on the top shelf and the carrots on the middle shelf until cooked through, 20-25 mins. IMPORTANT: The chicken is cooked when no longer pink in the middle.
Halfway through cooking, turn the carrots and add the garlic parcel to the baking tray to roast until soft, 10-12 mins.

Meanwhile, chop the potatoes into 2cm chunks (peel first if you prefer). Add to the pan of boiling water with 1/2 tsp salt. Simmer until you can easily slip a knife through, 15-20 mins.
Once cooked, drain in a colander and pop them back into the pan. Cover with a lid to keep warm.
Meanwhile, halve, peel and chop the red onion into small pieces.

Put the (now empty) frying pan back on medium-high heat with a drizzle of oil.
Once hot, add the mushrooms, onion and season with salt and pepper. Stir-fry until golden and softened, 4-5 mins.
Stir in the water for the sauce (see ingredients for amount) and red wine jus paste. Bring to the boil, then lower the heat and simmer until the sauce has reduced by half, 4-5 mins. Remove from the heat.

When the chicken is cooked, transfer to a board to rest for a couple of mins.
Once the garlic has cooled, cut the end with scissors, squeeze it out of the skin and mash with a fork. Add the garlic to the potatoes along with a knob of butter and a splash of milk (if you have some). Mash until smooth, then season to taste with salt and pepper.
Slice the chicken widthways, then serve on your plates with the mash and carrots alongside. Spoon over the mushroom sauce to finish.
Enjoy!