- Pre-heat oven to 180°C (160°C fan-assisted).
- Line the side and base of a loose bottom 20cm round cake tin with baking parchment, grease the sides of the tin so that the paper will hold.
- In a food processor, pulse the oat bars until finely ground. Mix the ground oats with the melted oil or butter. Press the oat mixture evenly onto the bottom and 2cm up the sides of the tin. Refrigerate to set.
- In a food processor or free-standing mixer beat the eggs, until smooth and fluffy. Beat in the lemon juice, maple syrup and vanilla. Add the 250g of mascarpone and ricotta cheese, and blend on a low speed until combined.
- Place the tin on a wire rack with a tray lined with a baking parchment or silicone mat — in case the tin leaks. Pour the mixture into the tin and bake for 15 minutes then reduce the oven temperature to 160°C (140°C fan-assisted) and bake for further 35 minutes. Then turn off the oven, leave the door ajar and leave for 10 minutes - it will continue to set as it cools. Finish cooling on a wire rack.
- When completely cooled, refrigerate the cake in the tin. For the topping, beat the mascarpone until smooth then add the maple syrup and vanilla.
- Remove the cake from the fridge, smooth the mascarpone cheese into the center of the cake and using the back of the spoon create a ‘wall’ around the edge. Place the raspberries in the middle, garnish with a few sprigs of mint if you like.
This smooth, creamy cheesecake can be baked up to 2 days ahead and refrigerated in the spring form tin. Decorate with the mascarpone and berries to serve.