For the black pea hummus, prepare the beans the day before you want to serve the dish. Rinse the dried peas thoroughly under cold running water. Place in a bowl and cover with cold water. Soak overnight in the fridge.
The next day, drain the peas and steam gently for an hour. In a conventional steamer, place water in the pan and bring to the boil. Set the steamer over the pan and turn down the heat. Check regularly to ensure the water level does not drop too much. In a steam oven, place the black peas in a tray and cover with 600ml/20fl oz cold water. Place in the steam oven and set to 120C with 100% humidity. Steam for an hour, then drain the peas again to remove the liquid.
In the meantime, preheat the oven to 220C/200C fan/Gas 7. Drizzle a little oil over the garlic and roast for 15-20 minutes, or until the cloves are soft and pale golden-brown.
Cut the bulb in half, squeeze out the soft, cooked garlic and pass through a sieve to create a purée.
When the peas are nearly tender, put both oils in a small pan and add the dried chillies. Heat gently to infuse the oils with the chilli (ensure the chilli flakes don’t burn in the oil), then set aside.
Reserve some peas for garnish and place the remainder in a food processor. Add the salt, treacle, lemon juice, tomato juice and a teaspoon of the garlic purée. Process on full speed until combined, then, with the motor running, pour in the warmed oils in a steady stream. Process until smooth.
Season the hummus with salt and pepper. You will have more hummus than required for this recipe, but any excess can be stored in the fridge in an airtight container for up to 3 days.
For the cauliflower, remove the leaves from the cauliflowers and set aside 4 of the yellow inner (yellow) leaves for the tempura.
Trim the stalks of the cauliflowers and shape into a point using a small knife.
Pour 1 litre/1¾fl oz water into a saucepan and season with salt and a pinch of caster sugar. Add the butter to the pan and bring to the boil. Blanch the tender cauliflower leaves for 30 seconds and refresh in ice-cold water. Remove the leaves and pat dry using kitchen roll. Set aside.
Add the tiny cauliflowers to the boiling water and cook for 3-4 minutes on a high heat (ensure the water boils rapidly). When the cauliflowers are tender, but still retain a little bite, place them on a tray lined with kitchen roll. Season the cauliflowers with salt and pepper and keep warm.
Preheat a deep-fat fryer to 180C.
For the tempura leaves, dust the blanched cauliflower leaves with cornflour, dip in the tempura batter and deep fry until crisp and golden-brown. Drain on kitchen roll and season with salt. Keep warm in a low oven until ready to serve.
For the spring onions, heat a non-stick frying pan over a high heat. Lightly brush the spring onions with oil then scorch them in the hot pan. Season with a little salt and freshly ground black pepper. Keep warm.
For the smoked onion sauce, preheat the oven to 200C/180C fan/Gas 6.
Place the whole onion on a baking tray and roast in its skin for approximately 1 hour until very soft. Remove from the oven and set aside to cool.
When the onion has cooled, carefully remove the skin and retain all the juices. Smoke the onion for 20 minutes.
Place all the remaining ingredients in a saucepan and bring to the boil. Pour into a liquidiser and add the smoked onion. Process until smooth, then pass through a fine sieve. Season with salt and pepper.
To serve, place a spoonful of black pea hummus in the middle of each warmed serving bowl and add some cooked black peas. Place the cauliflower on top of the hummus, point upwards, and spoon over some of the smoked onion sauce. Garnish with the scorched spring onion, ham and tempura cauliflower leaves. Finally sprinkle over the chive flowers and chopped chives. Serve immediately.