Roast the sirloin, then smoke over thyme and wood on the grill, and brush with the beef fat and horseradish oil whilst resting.
Then peel one large cucumber, blanch and refresh in ice water. Cut in the middle and season.
For the shiso vinegar, bring the white wine vinegar, sugar and water to the boil and then allow to cool to 50°C. Pour it over 40g of crusted shiso leaves and leave to infuse for two weeks. Then cut 10 baby cucumbers in length and place in a vac pac bag with some pickle liqueur and compress. Then slice the cucumbers and finish with horseradish oil and salt.
To make the cucumber gel, take two large cucumbers and blitz with 4g of salt and pass the juice, then slightly thicken with some Ultratex and season again with horseradish oil and chardonnay vinegar
For the beef sauce, take the roast beef trim and add a little butter, one sliced shallot, 50g button mushrooms and 50ml white wine, reduce. Then infuse with thyme and leave for 10 mins and add touch of sherry vinegar to taste.
Turn all the beef trimmings into chopped beef tartar, by mixing with reduced Worcester sauce, Dijon mustard and a cured egg yolk.
For the bone marrow custard, take the roasted bone marrow and mix with 100ml cream, 400g milk and four egg yolks in a pan. Slowly bring it to 80°C, and season with horseradish oil and lightly thicken with Ultratex.
Peel and slice raw baby cucumber and mix with chopped mint, vegetable oil and a little salt, then build up on top of the tartare.
To make the cucumber powder, burn cucumber skins in an oven at 220 °C for 45min-1 hour or until really black and dry, then allow to go cold and blend into a find powder. Dust on the tartare to finish.
Purple shiso leaves to finish the plate.