Strawberry-mallow cheesecake

First, make the shortbread base. Heat oven to 160C/140C fan/gas 3. Rub the butter into the flour and sugar until the mixture makes a sticky dough. You can do this by hand or in a food processor. Press evenly into the base of a non-stick 26cm springform tin and smooth with the back of a metal spoon. Prick all over with a fork, then bake for 25-30 mins until pale golden. Cool, then carefully oil the sides of the tin using kitchen paper.

To make the filling, soak the gelatine in cold water for a few mins to soften. Meanwhile, purée the strawberries in a food processor or with a hand blender until very smooth, then rub through a sieve to remove all the seeds. Pour the milk into a small pan and warm gently. Squeeze the gelatine of excess water, add to the milk, then remove from the heat and stir to dissolve. Cool.

Stir the strawberry purée, gelatine mixture, ricotta and sugar together until smooth. In a separate bowl, whisk the cream until it softly holds its shape, then fold into the strawberry mixture with three-quarters of the marshmallows.

Carefully pour onto the cooled base and scatter over the remaining marshmallows. Cover the tin with cling film and chill until firm, preferably overnight. Cheesecake can be made 2 days ahead if kept chilled.

Carefully remove the cheesecake from the tin. Decorate with extra berries and finish with a dusting of icing sugar.