Preheat oven to 350°F (175°C). Grease and line a 9-inch springform or round cake pan.
Make raspberry compote: simmer raspberries, 1.5 tbsp sweetener and lemon juice 3–5 minutes. Cool.
Combine streusel ingredients in a small bowl; set aside.
Whisk dry cake ingredients (almond flour, sweetener, baking powder, salt). In another bowl whisk egg, melted butter, sour cream, vanilla; fold into dry to make batter.
Beat cream cheese, egg, sweetener and vanilla until smooth.
Press two-thirds of batter into pan to form base. Spread cream cheese mixture over base. Dollop compote and swirl. Spoon remaining batter over cream cheese, spread gently. Sprinkle streusel on top.
Bake 30–38 minutes until top is golden and batter is set. Tent with foil if browning too fast.
Cool 30 minutes then chill at least 1 hour. Slice into 12 wedges and serve.