01 -
Heat the oven to 350°F and line a deep 9-by-9-inch pan with parchment.
02 -
Mix graham crumbs, one-quarter cup sugar and melted butter. Press into an even base and bake for eight to ten minutes.
03 -
Let the crust cool slightly while preparing filling. Beat softened cream cheese with the separate three-quarter cup sugar until smooth.
04 -
Add eggs one at a time on low speed.
05 -
Mix in plain pumpkin puree, vanilla, spice and the optional tablespoon of flour just until combined. Spread over the crust with room below the pan rim.
06 -
Bake, checking from twenty-five minutes and continuing until the edges are set, the center no longer ripples and the filling reaches 160°F. Cool briefly, refrigerate within two hours and chill at least four hours before cutting.