3.Preheat oven to 180°C/350°F. Grease deep 22cm (9-inch) square cake pan with butter; line base and sides with baking paper.
4.Halve cherries, remove seeds.
5.Beat butter, extract and sugar in small bowl with electric mixer until light and fluffy. Beat in eggs, one at a time, then beat in sour cream. Transfer mixture to large bowl. Stir in sifted flours and ground almonds.
6.Spread half the cake batter into pan, top with half the cherries and half the almond crumble. Repeat layers. Bake cake about 1 hour 10 minutes. Turn cake, top-side up, onto wire rack to cool.
We prefer the flavour of fresh cherries in this cake, but frozen can be used. Leave frozen cherries whole and don’t thaw before using. Natural sliced almonds still have the skin on them. They are available from health-food stores and major supermarkets. Almond paste is available from major supermarkets and good delicatessens; marzipan can be used instead.