In a bowl, mix together the chopped walnuts, chopped dates, and melted butter.
Press the mixture into the bottom of a 9-inch springform pan and bake for 10 minutes.
In another bowl, beat the cream cheese with 1 cup of sugar until creamy.
Add the eggs, one at a time, beating well after each addition.
Stir in the vanilla extract.
Pour the cream cheese mixture over the crust and bake for 50-55 minutes or until the center is almost set.
Remove from oven and let cool to room temperature. Refrigerate for at least 3 hours or overnight to set.
In a small saucepan, combine the pureed strawberries, blood orange juice, grapefruit juice, cornstarch, and 1/4 cup of sugar. Cook over medium heat, stirring constantly, until the mixture thickens.
Let the sauce cool to room temperature.
Serve the cheesecake with the strawberry sauce on top.