Tandoori-spiced beef Wellington with smoked creamed potatoes and tandoori gravy

Begin by blanching the tarragon for the herb oil, and then transferring it to iced water. Once cool, squeeze out as much water as you can. Add the blanched herbs to a Thermomix along with all the remaining tarragon oil ingredients except the salt. Blend and heat to 80°C

Once at temperature, blend in the salt and pass the oil through a muslin cloth

Pour the oil into a sealed piping bag and let it hang overnight so that the cloudy substances settle at the bottom of the point. The next day, get rid of the solids and pour off the oil

Mix all the dry spices for the tandoori spice mix in a mixing bowl

Place the fillet of beef on a tray and generously sprinkle the spices over the beef until it is completely coated. Dust off the excess

Cover and refrigerate the beef for 24 hours

For the mushroom duxelles, pulse the mushrooms in a food processor until they are broken down to a paste. Remove from the blender and set aside

Blend the ginger and garlic into a smooth paste

Heat a wide-based flat pan on a medium-high heat and add the butter. Once the butter is frothy, add the shallots and thyme and sweat until golden brown

Add 50g ginger-garlic paste and cook for 1 minute, then add the mushroom paste. Cook until all the water from the mushrooms has evaporated and mushrooms start to form a thick paste

While the mushrooms are cooking, add the double cream to another pan

Bring the cream to the boil over a medium-high heat, whisking constantly. Keep whisking and cooking until the cream is reduced to about 100g. If you don’t whisk the cream then it will catch and burn

Once the mushrooms are ready, mix them with the reduced cream and adjust the seasoning with salt. Cook for a further 5 minutes to make sure all the water has evaporated

Spread the duxelles on a flat tray, cover and chill. Leave in the fridge until needed for assembly

To make the gravy, place a wide-based saucepan on a medium heat and add a generous knob of butter. Once the butter is frothy, add the reserved beef trimmings and caramelise until dark golden brown

Remove the trimmings and then add the onion. Cook until dark golden brown

Add 70g ginger-garlic paste you made earlier and cook for a minute, then add all the spices

Keep cooking for a further 2 minutes, then add the caramelised beef trimmings and both stocks

Bring to the boil and skim off any scum

Cover with tin foil and cook for 45 minutes 

After 45 minutes remove the tin foil. Skim as much scum as possible

Pass the gravy through a colander and then through a fine mesh strainer into a clean pan

Place back on the heat and bring to a boil. Keep skimming and cooking until it has reduced more than by half. Emulsify in the butter

Pass through muslin and then set aside until ready for service

Preheat the oven to 180°C for the potato purée

Cook the potatoes whole in the oven until tender all the way through, about 1 hour

Once the potatoes are cooked, cut them in half and scoop out the flesh. Pass the potato flesh through a ricer

While the riced potato is hot, add the butter and mix in with a wooden spoon

The butter will split, so add a splash of milk to help it emulsify, followed by the smoked oil and salt to taste

Mix well then keep warm in a piping bag until needed

Melt the butter for the carrot purée in a pan, add the carrots with salt and sugar and sweat down until they release their own liquid

Cook until the carrot liquid has evaporated

Add the water and cook until that has mostly evaporated

Cover half the pan with the lid, and keep cooking until the carrots are super soft and there is no liquid left

Blend the carrot purée and then keep warm in a piping bag until needed

For the pancakes, blend the milk and eggs together using a hand blender or a whisk (a hand blender is better)

Add the flour and salt, and then blend to form a smooth batter. Pass through a conical strainer

Add a dash of oil to a medium non-stick frying pan, then heat up over medium heat. Wipe any excess oil away with a kitchen towel

Reduce the heat and then add a ladle of batter into the pan. Spread evenly into a thin layer, and then pour the excess back into the bowl

Once the pancake is cooked, remove the pancake from the pan and repeat with the remaining batter

Allow the pancakes to cool and keep them covered until ready to assemble

Remove the beef from the fridge, and lightly coat it in oil

Heat a non-stick pan and add a little oil. Once the oil starts smoking, flash-fry the beef until caramelised on all sides

Drain the beef on a kitchen towel, and then set aside

Preheat a fan oven to 200°C

Lay out a large piece of cling film on a work surface

Lay out six pancakes, overlapping at the edges. Stick the overlapping edges down with some egg wash

Spread the duxelles evenly on the pancakes

Place the beef fillet in the centre of the duxelles

Roll the pancakes around the fillet, making use of the clingfilm for support, but ensuring the cling film does not get folded into the pancakes

Trim off any excess, then tightly fold the cling film around the beef and place in the fridge to rest

Once rested, spread another piece of cling film on a work surface. Place the puff pastry sheet onto the clean piece of cling film and brush it with egg wash

Remove the cling film from around the pancake-wrapped beef and place it on the pastry. Roll the puff pastry tightly around the fillet, using the cling film to help you, just as you did with the pancakes. Trim any excess pastry, and set aside to use to form the lattice. Wrap the wellington tightly in cling film

Rest the Wellington in the fridge. Meanwhile, use a lattice roller to cut the extra pastry into a lattice shape

While the beef chills, make the fried onion topping for the potato. Mix a pinch of turmeric into the cornflour to turn it light yellow

Lightly dust the onion in the cornflour mixture

Heat up the vegetable oil to 180°C

Fry the onion until it is crispy, and then remove using a wire strainer. Drain on paper towels

Once drained, mix the crispy onion with the chives

Remove the chilled Wellington from the fridge. Brush with egg wash, neatly organise the lattice over the pastry and then egg wash again

Preheat the oven to 220°C

Place the Wellington on a baking tray lined with non-stick paper. Place in the oven with a meat thermometer inserted in the wellington

Cook until the internal temperature reaches 42°C for a rare beef wellington 

Remove from the oven. Allow to rest, but keep the thermometer inserted

While the Wellington rests, pipe the carrot purée around the edge of each plate. Garnish each serving of potato with the crispy onion mix

Carve the Wellington and place a slice on the plate. Serve the gravy hot on the side