To make the pastry, put the flour in a bowl, add the butter and lard, and rub together with your fingertips until the mixture resembles breadcrumbs. Using a round-bladed knife in a cutting motion, combine the egg with the mix until a pastry ball forms. Turn out on a lightly floured surface and quickly knead until even and smooth, then wrap and chill for 30 minutes.

Heat the oven to 190°C/gas 5.

Roll out the pastry and line a 30cm push-up-bottom tart case. Mix together the cream and Dijon mustard and spread over the pastry base. Arrange the sliced tomatoes in the case, season, and scatter thyme leaves — stripped from the stalks — over the top.

Bake for 40 minutes. Drizzle with a little olive oil and serve warm or cold.