1. Preheat oven to 180/350/Gas 4. Grease and base line a swiss roll tin 28cms x 18cms/11" x 7" with greaseproof paper.
2. Put the butter, sugar and lemon rind into a mixing bowl and beat until creamy. Beat in the vanilla essence, ground almonds and egg. Finally add the flour and mix well.
3. Transfer to the prepared tin, spread evenly with the back of a spoon dipped in flour or fingertips dipped in flour. Prick top with a fork.
4. Bake for 15 minutes until pale golden and just firm to the touch. Allow to cool.
5. Spread the cookie base with a layer of jam. Cut the marshmallows in half using a scissors, arrange. Arrange them, cut side down in an even layer over the jam. Preheat the grill to medium.
6. Put the tin under the grill for 2 minutes until marshmallows are melted and pale golden. Remove from under the grill and press down each marshmallow with the back of a spoon to form a layer. Return to the grill for a further minute until the surface is very toasted.
7. Leave to cool. To serve, lightly dust with icing sugar and cut into squares or bars and remove from the tin.

Recipe Notes:

A delicious contrast of textures and flavours