Preheat the oven to 350 degrees. Either grease and flour or spray with baking spray a 9x9 baking pan.
To make the streusel, in a medium bowl, stir in flour, oats, brown sugar, and salt. Cut cold butter into small pieces and add to the mixture. Using a pastry cutter or fork, combine the streusel mixture until it consists of small crumbs. Stir in the chopped pecans.
Press 2 cups of the streusel mixture into the bottom of an 9x9 baking pan for the crust.
In a separate bowl, beat the cream cheese and granulated sugar until smooth. Add the egg, vanilla, and lemon juice and mix to combine. Pour evenly over the crust. Spread the cranberry sauce over the top of the cheesecake layer.
Sprinkle the remaining streusel mixture evenly over the top.
Bake at 350F for about 25 - 30 minutes. Allow to cool completely before serving. These can be enjoyed immediately after cooling or, refrigerating for a few hours (recommended).