Put the cream cheese in the large bowl of an electric mixer. Mix on low speed until smooth, about 1 minute. Add the sugar and mix until smooth and creamy, about 1 minute. Mix in the flour. Add the eggs, two at a time, mixing the batter smooth after each addition. Stop the mixer and scrap the sides of the bowl twice during this mixing. Mix in the vanilla and lemon juice. Mix in the whipping cream. Put 3/4 cup of the batter into a small bowl. Stir in the chocolate truffle sauce