Sour cream, apple and blackberry tart recipe

Is there a lovelier feeling, a happier sight at the close of summer than, as Sylvia Plath wrote: “Nobody in the lane, and nothing, nothing but blackberries”; picking with no one and nothing to hurry you in the precious dimming days, when your skin knows the holidays are coming to an end.

Autumn prefers tarts to unfurl a roof to become pies, so this is for days when you need a little summer, even in October.

Serves 6-8
butter 225g cold, diced
plain flour 250g, plus more for rolling
sugar 4 tbsp
sour cream 120g
bramley apples 5
blackberries 100g

Place 200g of the butter, the flour and 1 tablespoon of the sugar in a food processor and pulse a few times until the mixture resembles coarse breadcrumbs. By all means, rub the ingredients together in a bowl using your fingertips instead, if you prefer.

Add the sour cream and pulse or mix until the dough starts to come together, stopping just before it forms a ball. If it is still crumbly and does not bind, add a little cold water.

Form the dough into a flat disc, wrap in baking parchment and chill for 20-30 minutes before using.

While the pastry is resting, core, peel and dice 3 of the apples. Place them in a pan over a medium heat with the blackberries, the remaining 25g butter, 2 tablespoons of the sugar and 1 tablespoon of water, and cook for 5-7 minutes until the apples are tender. Remove from the heat and mash everything roughly with a fork.

Roll the pastry on a surface dusted with flour to about 3mm thick. Line a 25cm tart tin with the pastry, leaving about 5mm hanging over the edge of the tin, then allow it to rest for 20 minutes in the fridge.

Preheat the oven to 170C fan/gas mark 5. Cover the base of the pastry with a circle of baking parchment and fill with baking beans, then bake for 5 minutes. Remove the baking beans and parchment and return the tart case to the oven for 5 minutes until lightly golden and dry to the touch. Trim the edge of the pastry to make it neat, or leave it rough and ready if you prefer.

Core, peel and thinly slice the remaining apples. Spread the apple and blackberry puree over the base of the tart, then arrange the apple slices over the top and sprinkle with the remaining tablespoon of sugar.

Bake for about 20-25 minutes until the apples are just golden brown at the edges but not collapsing. Remove from the oven and serve with whichever form of cream or yoghurt takes your heart’s desire.

From Sour: The Magical Element That Will Transform Your Cooking by Mark Diacono (Quadrille, £25)