Tomato Tart with Caramelised Red Onion Recipe

(29 ratings)

tomato tart
Preparation Time10 mins
Cooking Time1 hours 10 mins
Total Time1 hours 20 mins
Cost RangeCheap
Nutrition Per PortionRDA
Calories551 Kcal28%
Fat28 g40%
Saturated Fat12 g60%

This tomato tart with caramelised red onions is very simple to prepare and makes the most of the different varieties of tomatoes in season. The sweet caramelised onions bring out the natural flavour of the tomatoes to give a delicious and crowd-pleasing tart that is the perfect dish for al fresco lunches or a late summer dinner party starter. Once you’ve made your caramelised onions, which can be prepared in advance, this tomato tart couldn’t be easier to prepare. Ready made puff pastry can be bought in most supermarkets and is much less of a hassle than making your own. The all-butter varieties give the best results, but pastry made with margarine can be used to make this recipe suitable for vegans.

British tomatoes are in season from June until October, and this tomato tart is a great way to use up a surplus of seasonal tomatoes. Our recipe for delicious slow roasted tomatoes is another great way to celebrate this healthy and flavour packed ingredient. For more ideas with tomatoes have a look at our tomato recipe collection.



  1. Cook the onions in a sauté pan with the oil until softened, about 40 mins. Add the vinegar and sugar, stir well until the sugar has dissolved and set aside to cool.
  2. Heat the oven to 200C. Roll out the pastry to about ½cm thick to a rectangle and lightly score with a knife 3cm in from the edge. Spread the onions over the pastry base and top with the sliced tomatoes. Bake the tart for 25 mins or until browned and crisp at the edges. Serve immediately with a green salad.


  • 5 red onions, thinly sliced
  • 1tbsp olive oil, plus extra to drizzle
  • 2tbsp balsamic vinegar
  • 2tbsp brown sugar
  • 375g all-butter puff pastry
  • 500g tomatoes, thickly sliced
Jane Curran

Jane Curran is a freelance food editor, stylist, writer and consultant based in Cape Town. Former food director of TI Media & woman&home. All about food, wine (dipWSET), gardening and the Arsenal.