Pre-heat oven: 185°C / 165°C (fan) / Gas Mark 4 ½ / 365°F
Melt the white chocolate and butter (microwave for 45-60secs, 15secs at a time), until smooth and fully combined.
In a large bowl, beat the eggs until foamy and then add the sugar and almond extract, beating until smooth.
Drizzle in the melted white chocolate and butter mixture, beating together until your mixture is combined.
Sift the flours into the mix and add the ground almonds and salt. Fold these into the mixture gently.
Stir in the white chocolate chips until just spread evenly throughout.
Line a tin with greaseproof/baking paper and pour half of the mix into the pan, smoothing into an even layer.
Microwave the jam for 15secs and then gently spread this across the blondie mix, leaving an inch/few cm border at the edges.
Cover the jam layer with the remaining blondie mix, smoothing the top gently and sprinkling flaked almonds on top (if using).
Bake for 25-30mins until it no longer wobbles and has a golden top. It will harden further as it cools. Once cooled, remove from the tin and cut into squares.