To make the pastry, rub together the flour, baking powder, sugar and butter till the mixture resembles breadcrumbs. Add the egg yolk, vanilla essence and milk and mix to soft dough. Grease a 23cm/ 9 inch flan tin, and line with just over half the pastry. Prick the pastry all over with a fork. To make the ricotta filling, mix together the ricotta cheese, sugar and lemon zest. Gently fold in the broken biscuits and sliced almonds, and use this mixture to fill the pastry case. Spread the filling out evenly, and then use the remaining piece of pastry to cover the top of the tart. Prick the top of the tart with a fork, and bake for 30 minutes at 190°C, or until the pastry is golden brown. Remove the ricotta tart from the oven and leave to cool completely in the tin. When the tart is cold, carefully remove it from the flan tin and place it on a large serving plate. Decorate the top of the tart by arranging the whole strawberries on the top. Heat up the glazing jelly in a saucepan, and carefully glaze the strawberries all over using a pastry brush. Chill the ricotta and almond tart with strawberries well before serving.