1. Preheat oven to 350°F with the rack in
the middle position. Coat the inside of
a 9-inch square baking pan with the
softened butter or nonstick cooking
spray. Line with parchment paper, leaving
a 1- to 2-inch overhang (this will assist in
removing the bars after they have baked
and chilled). Reserve.
2. Prepare the crust. Put graham cracker
crumbs, sugar, cinnamon, salt, and
melted butter in a small mixing bowl.
Mix on Speed 1 until the mixture comes
together. Pat crumb crust evenly into the
bottom of the prepared pan, using the
bottom of a glass, if necessary, to make it
even. Put in the preheated oven and bake
for about 8 to 10 minutes, until the crust
is just set. Allow to cool while preparing
the filling. Reduce oven temperature to
250°F.
3. Wipe the beaters of crumbs. Put the
cream cheese into a large mixing bowl.
Starting on Speed 1 and increasing to
Speed 3, mix until very smooth – you
want to be sure there are no lumps.
Scrape the mixing bowl and beaters.
While mixing on Speed 3, gradually add
the sugar, about ¼ cup at a time, and the
salt, mixing until very smooth. Add the
eggs, one at a time, mixing on Speeds 2
to 3, being sure each is fully incorporated
into batter before adding the next. Scrape
down the bowl and beaters and then add
the sour cream and vanilla extract, mix on
Speeds 2 to 3 until combined.
4. Transfer the cream cheese filling to the
pan, on top of the cooled crust, and then
dollop the blueberry preserves on top.
Using the tip of a knife, or a toothpick
or skewer, swirl in the preserves to
make an attractive design. Top with the
blueberries, pressing in slightly.
5. Put the filled pan into the preheated oven
and bake until just set, about 60 to 65
minutes.
6. Remove and cool to room temperature.
Cover with plastic wrap and chill
overnight prior to removing from the pan,
cutting, and serving.