Preheat oven to 150°C fan / 170°C conventional / Gas Mark 3 to 4. Grease and line the tin.
Beat butter and sugar for the base together, then mix in the flour with a spatula until it forms a soft, crumbly dough. Press into the tin.
Spread over the raspberry jam.
Toss the quartered cherries in 1 tsp flour. If the sultanas are sticky, toss them lightly too.
For the topping, beat butter, sugar, remaining flour, eggs, ground almonds and almond extract until smooth. Add 1 tbsp milk if the mixture looks too thick.
Fold in the cherries and sultanas. Spoon over the jam and spread evenly. Scatter the extra cherries on top.
Bake for 35 to 45 minutes, until golden, risen and firm to the touch. Cool fully in the tin, sprinkle with caster sugar and cut into slices.
Variations in comments
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