Preheat oven to 180 C/ gas mark 4/ 160 C fan and grease and line the base of a 9 inch square cake tin with a removable base.
Prepare the shortbread base by processing the flour, butter, sugar and salt in a food processor until it forms clumps. Press into a thin layer in the bottom of the cake tin and bake for 12 minutes until golden. Set aside to cool.
Prepare the crumble topping by mixing the almonds, brown sugar, flour and cinnamon together. Pour over the melted butter and stir until combined. Set aside.
Prepare the cake batter by creaming the butter and golden caster sugar together until light and fluffy.
Add the eggs, one at a time, beating well after each addition. Add the vanilla extract.
Stir in the ground almonds, flour, baking powder and salt and combine well with a wooden spoon. Add the milk to make a soft dropping consistency.
When the shortbread base has cooled, spread over the cherry jam leaving a 1 cm gap around the edges of the pan so the jam doesn't burn to the pan.
Gently spoon the cake batter over the top of the jam and smooth over the top.
Drop the cherries all over the top of the cake batter and then sprinkle with the crumble topping.
Bake for 45-60 minutes, covering with foil towards the end of baking if you feel the top is browning too much.
Leave to cool in the tin for 10 minutes before transferring to a wire rack to cool completely.
Cut into 16 squares and store in an airtight container.