There’s a lot to love about this tart. The silky-smooth, almost custard-like filling, the unctuous caramelised onions and the sharp, yet sweet blue cheese that finishes it off. Tarts are fantastic. They make great lunch or dinner fare and they travel well, making them perfect for picnics and potluck meals. Recipe, styling & photos Emma Boyd

Serves 6–8, Prep Time 20 minutes, Cook Time 45 minutes

• Pastry
• 300 g flour
• ½ tsp salt
• 125 g butter, cut into small cubes
• 1 egg
• 6–7 tbsp crème fraîche or Greek yoghurt

Filling

• 4 tbsp olive oil
• 4 large onions, quartered, thinly sliced
• 6 eggs
• ½ cup cream
• ⅓ cup crème fraîche
• 2 tsp thyme leaves stripped from stalks
• 65 g blue cheese

Preheat the oven to 180°C. Put the flour, salt and butter into a food processor and process until the butter has been incorporated into the flour. Add in 1 egg and process again. Lastly add in the crème fraîche/yoghurt tablespoon by tablespoon until the mixture starts to fall away from the sides of the food processor. If a bit of the mixture squeezed between your fingers holds together then it is ready.

Turn the pastry out onto a clean, floured bench and roll out until it is large enough to line a 30 cm fluted tart dish. Line the dish with the pastry, prick with a fork then put into the fridge for 30 minutes. Remove from the fridge and blind-bake the pastry for 15 minutes or until golden brown.

For the filling, heat the olive oil in a heavy-bottomed frying pan over a medium-high heat. Add in the onions and cook until dark brown and caramelised. This will take 20 minutes or so. Set aside. Put the remaining 6 eggs, cream, crème fraîche and thyme into a large bowl, season well with sea salt and freshly ground black pepper and using a fork whisk well to combine. Stir in the onions and pour this mixture into the pastry shell. Dot over the blue cheese and bake for 20 minutes or until just set. Remove from the oven. Serve with a crisp green salad.