Combine the butter, almond meal, desiccated coconut and Natvia and stir to combine.
Combine the cream cheese, Natvia, lemon zest, lemon juice and vanilla in the bowl of a food processor and process until smooth. Sift in the flour and pulse 2-3 times to combine. Add the eggs one at a time and pulse to combine between each addition. Add the sour cream and process until combined and smooth.
Pour over the base and then pour over the blueberry puree. Swirl through the cake using a skewer. Cover with aluminium foil or a lid and place in the oven for about 25 minutes. Lower the heat to 100C and continue to bake for about 45-50 minutes, removing the cover in the last 5 minutes or so. Turn the oven off and stand the cake in the oven for about 2 hours or overnight. Place in the refrigerator to chill before serving