Ingredients
Streusel
225g (8oz / 2 sticks) unsalted butter, melted, plus extra for greasing
350g (12oz / 2 3/4 cups) plain (all-purpose) flour
200g (7oz / 1 cup) caster (superfine) sugar
1⁄4 teaspoon fine sea salt
4 tablespoons rolled oats
Cheesecake
565g (20 oz) full-fat cream cheese, at room temperature
120ml (4fl oz / 1⁄2 cup) sour cream, at room temperature
200g (7oz/1 cup) caster (superfine) sugar 2 tablespoons cornflour (cornstarch)
2 teaspoons vanilla bean paste
finely grated zest of 2 lemons
2 large eggs
For the Raspberry Filling
3 tablespoons raspberry jam
300g (10 1⁄2oz) fresh raspberries
Method
Preheat the oven to 180°C (350°F), Gas Mark 4. Lightly grease a 9×13 brownie tin, then line with a strip of parchment paper that overhangs the two long sides of the tin. Secure the paper in place with two metal clips.
For the streusel, mix together the flour, sugar and salt in a large bowl. Gradually drizzle in the melted butter, stirring with a fork to combine until the mixture has formed clumps, then tip about two-thirds of the mixture into the prepared tin and spread out evenly. Use a glass to compact it into a flat layer. Dock all over with a fork and then freeze for 10 minutes. Mix the remaining streusel with the oats and refrigerate until needed.
Bake the base for 20 minutes, or until just starting to brown, then remove and set aside.
To make the cheesecake, place all the ingredients into a large bowl and mix together until smooth and evenly combined. Pour the cheesecake mix evenly over the base.
For the filling, gently warm the jam in a pan until loose, then remove from the heat and mix with the raspberries, coating evenly. Dot the raspberry mixture over the cheesecake, then crumble the reserved streusel evenly over the top.
Bake for 35–40 minutes, or until the streusel is lightly browned.
Leave to cool in the tin for an hour, then refrigerate for at least 4 hours, before cutting into squares to serve.
Store in a sealed container in the refrigerator for 4 days.