Red Onion Tart Recipe with Watercress Pesto & Roasted Cherry Tomatoes

This tasty vegan Red Onion Tart is bursting with flavour, and enhanced by a wonderful watercress pesto made with hazelnuts for a nutritious and delicious twist.  Serve with a salad for a light lunch, or with potatoes and vegetables for a more substantial dinner.

Red Onion Tart with Watercress Pesto & Roasted Cherry Tomatoes

Serves 4


4 red onions, finely sliced
1 tbsp red wine vinegar
1 tbsp sugar
75g watercress
½ a clove of garlic, finely chopped
35g toasted hazelnuts
100ml extra virgin olive oil plus a bit extra
1 head broccoli, cut into small florets
1 sheet of puff pastry (suitable for vegans, we used Jus-Rol)
2 sprigs fresh thyme
250g cherry tomatoes on the vine
Salt and pepper


1. Heat a splash of olive oil in a heavy-based saucepan over a medium heat.

2. Once the oil is hot, fry the sliced red onions for 5 minutes until beginning to caramelise.  Stir occasionally as they cook.

3. Add the red wine vinegar and sugar, then reduce heat to low and continue to cook until the onions are completely softened, and the liquid has reduced to a sticky consistency (about 15 minutes).  Then remove from the heat and allow to cool.

4. Next make the pesto by adding the watercress, garlic and hazelnuts to a food processor with the olive oil.  Blend for a couple of minutes then remove the lid and scrape down the sides.

5. Pulse a few times to ensure no big chunks are missed.  Season to taste then set the pesto aside.

6. Place the broccoli florets into a bowl and drizzle with a little olive oil.  Add a pinch of salt and pepper then toss to coat evenly.

7. Preheat the oven to 200°C.  Take your pastry sheet and cut it into 4 equal rectangles.  Place the rectangles on a baking tray.  Spread the pesto thickly onto the pastries, leaving a 1cm border around the edge.

8. Use a spoon to scatter the red onion mixture over the top evenly.  Dot with the broccoli florets then put the baking tray into the oven.

9. Bake for 10-15 minutes or until the pastry around the edges is risen and golden.

10. While the tarts cook, prepare the tomatoes.  Use a pair of scissors to snip them into four equal sized portions, keeping as many tomatoes attached to the vine as possible.

11. Place onto a baking tray, drizzle with olive oil and season with a little salt and pepper.  Place into the oven with the tarts for the last eight minutes of cooking.

12. Finally remove your tarts and tomatoes from the oven and serve hot.  Sprinkle with thyme before serving.

For a different variation why not try swapping the broccoli for asparagus, kale or green beans.

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Want more vegan pie recipes?

Mushroom, Potato and Watercress Pie
Smoky Beetroot Tart
Mushroom and Leek Pie
Chestnut and Beetroot Wellingtons

Want more vegan watercress recipes?

Smoked Tofu and Watercress Cannelloni
Black Bean and Watercress Burger
Baked Sweet Potatoes with Watercress, Tahini Sauce and Roasted Chickpeas
Turmeric, Watercress and Carrot Soup
Barbecued Peach Salad

Recipe c/o Love Watercress

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