Ingredients

For the pastry:100g butter 200g wholemeal flour Pinch salt and pepperCold water1 egg, beaten For the beetroots:3 baby beetroots Pinch salt .

For the filling:2 medium onions, chopped2 cloves garlic, crushed 75g butter 200g watercress 200g hot-smoked trout, flaked Large bunch chives, chopped Maldon sea salt & crushed black peppercorns, to season3 eggs 200ml double cream 1tbsp sour cream 4tsp garlic & horseradish mustard

For the vinaigrette:1 shallot, very finely chopped White wine vinegar/cider vinegar1 tsp honeyBunch tarragon, blanched and refreshed ½ garlic clove, pureed Rapeseed oil1tsp honey mustard

For the Horseradish Cream :2tbsp sour cream 2-3tsp finely grated fresh horseradish3 sprigs lemon thyme

Instructions

1.For the pastry, rub the butter into the flour with a pinch of salt & a grind of pepper.

When the mixture resembles fine breadcrumbs, add enough cold water to bind into a pliable dough. Rest in the fridge for 30 minutes.

2. Preheat the oven to 180ºC. Roll out onto a lightly-floured surface & line a 20cm fluted flan tin. Prick all over with a fork, brush with egg & bake for 30-35 minutes.

3. Boil the baby beetroot in water with a pinch of salt for approximately 30 minutes.4. Turn the oven down to 150ºC. For the filling, prepare the onions & garlic and fry the onion in butter until golden and sticky, adding the garlic about halfway through. Turn off the heat.

5. Trim the watercress and blanch in boiling water for 1 minute, then plunge into iced water. Squeeze well and blot on absorbent paper, then chop and add to the cooling onions. Flake the trout & chop the chives.

6. Gently whisk the eggs with the cream, sour cream & mustard. Season with salt & lots of black pepper, then add the trout & watercress mixture and the fried onions, mix and pour gently over the tart. Bake for 55-60 minutes. The tart is ready when the centre is just set, but still has a slight wobble to it.

7. Remove the tart from the oven & leave to cool.

8. Remove the stalks from the watercress and spin the leaves in a salad spinner to remove all excess water. Dry on kitchen paper if necessary.9. Whisk the vinaigrette ingredients, minus the mustard, together in a bowl, then toss the leaves with a few spoonfuls of it just before serving.

10. Cut the tart into wedges. Serve one wedge on the plate and place the beetroot next to it. Top with a spoon of the vinaigrette and spoon on some sour cream. Top with the grated horseradish and lemon thyme. Arrange the dressed watercress next to it. Add the mustard to the rest of the vinaigrette and drizzle around the plate.